Page 3
page 3 IMPORTANT Installation, Commissioning, Service & Repair This appliance must be installed in accordance with the manufacturer's instructions and the regulations in force. Read the instructions fully before installing or using the appliance. In GB, this must be carried out by a competent person as stated in the Gas Safety (Installation & Use) Regulations. Definition of competence: A person who works for a Gas Safe registered company and holding current certificates in the relevant ACS modules, is deemed competent. In IE, this must be carried out by a competent person as stated in I.S. 813 "Domestic Gas Installations". The addition of anything that may interfere with the normal operation of the appliance without express written permission from the manufacturer or his agent could invalidate the appliance warranty. In GB this could also infringe the Gas Safety (Installation and Use) Regulations. Warning Check the information on the data plate is compatible with local supply conditions.
Page 4
All Gas Safe registered engineers carry an ID card with their licence number and a photograph. You can check your engineer is registered by telephoning 0800 408 5500 or online at www.gassaferegister.co.uk The boiler meets the requirements of Statutory Instrument " The Boiler (Efficiency) Regulations 1993 No 3083" and is deemed to meet the requirements of Directive 92/42/EEC on the energy efficiency requirements for new hot water boilers fired with liquid or gaseous fuels: Type test for purpose of Regulation 5 certified by: Notified Body 0085. Product/Production certified by: Notified Bodies 0085 & 0086. For GB/IE only. Legislation This company declare that no substances harmful to health are contained in the appliance or used during appliance manufacture. The appliance is suitable only for installation in GB and IE and should be installed in accordance with the rules in force, and only used in a suitably ventilated location. In GB, the installation must be carried out by a Gas Safe Registered Installer. It must be carried out in accordance with the relevant requirements of the: Gas Safety (Installation & Use) Regulations. The appropriate Building Regulations either The Building Regulations, The Building Regulations (Scotland), Building Regulations (Northern Ireland). The Water Fittings Regulations or Water Byelaws in Scotland. The Current I.E.E. Wiring Regulations. Where no specific instructions are given, reference should be made to the relevant British Standard Code of Practice. In IE, the installation must be carried out by a competent Person and installed in accordance with the current edition of I.S. 813 'Domestic Gas Installations', the current Building Regulations and reference should be made to the current ETCI rules for electrical installation. All systems must be thoroughly flushed and treated with inhibitor (see section 6.2). Codes of Practice refer to the most recent version In GB the following Codes of Practice apply: Standard Scope BS 6891 Gas Installation. BS 5546 Installation of hot water supplies for domestic purposes. BS EN 12828 Heating systems in buildings. BS EN 14336 Installation & commissioning of water based heating systems. BS 6798 Installation of gas fired hot water boilers. BS 5440 Part 1 Flues.
The following advice should be adhered to, from when first handling the boiler to the final stages of installation, and also during maintenance. Most injuries as a result of inappropriate handling and lifting are to the back, but all other parts of the body are vulnerable, particularly shoulders, arms and hands. Health & Safety is the responsibility of EVERYONE. There is no 'safe' limit for one man each person has different capabilities. The boiler should be handled and lifted by TWO PEOPLE. Do not handle or lift unless you feel physically able. Wear appropriate Personal Protection Equipment e.g. protective gloves, safety footwear etc. Preparation Coordinate movements know where, and when, you are both going. Minimise the number of times needed to move the boiler plan ahead. Always ensure when handling or lifting the route is clear and unobstructed. If possible avoid steps, wet or slippery surfaces, unlit areas etc. and take special care on ladders/into lofts. Technique When handling or lifting always use safe techniques keep your back straight, bend your knees. Don't twist move your feet, avoid bending forwards and sideways and keep the load as close to your body as possible. Where possible transport the boiler using a sack truck or other suitable trolley. Always grip the boiler firmly, and before lifting feel where the weight is concentrated to establish the centre of gravity, repositioning yourself as necessary. See the 'Installation' section of these instructions for recommended lift points. Remember The circumstances of each installation are different. Always asses the risks associated with handling and lifting according to the individual conditions. If at any time when installing the boiler you feel that you may have injured yourself STOP !! DO NOT 'work through' the pain you may cause further injury. IF IN ANY DOUBT DO NOT HANDLE OR LIFT THE BOILER OBTAIN ADVICE OR ASSISTANCE BEFORE PROCEEDING !! page 5 CONTENTS 1.0 Introduction 2.0 General Layout 3.0 Appliance Operation 4.0 Technical Data 5.0 Dimensions and Fixings 6.0 System Details 7.0 Site Requirements 8.0 Flue Options 9.0 Plume Displacement 10.0 Installation 11.0 Commissioning 12.0 Completion 13.0 Servicing 14.0 Changing Components 15.0 Setting the Gas Valve 16.0 Electrical...
1.0 Introduction 1.1 Description 1. The Baxi Duotec Combi HE A is a fully automatic gas fired wall mounted condensing combination boiler. It is room sealed and fan assisted, and will serve central heating and mains fed domestic hot water. 2. The boiler is set to give a maximum output of : 24 models 24 kW DHW 21 kW CH (Condensing) 28 models 28 kW DHW 25.9 kW CH (Condensing) 33 models 33 kW DHW 30.3 kW CH (Condensing) 40 models 40 kW DHW 34.4 kW CH (Condensing) 3. It is designed for use on Natural Gas (G20). 4. The boiler is suitable for use only on fully pumped sealed heating systems. Priority is given to domestic hot water. 5. The boiler data badge gives details of the model, serial number and Gas Council number and is situated on the inner door panel. It is visible when the case front panel is removed (Fig. 1). 6. The boiler model name and serial number are also shown on the information label on the underside of the facia. This is for user reference. 7. The boiler is intended to be installed in residential / commercial / light industrial E.M.C. environments on a governed meter supply only. 8. The boiler must be installed with one of the purpose designed flues such as the standard horizontal telescopic flue kit, part no. 5118069. 9. All systems must be thoroughly flushed and treated with inhibitor (see section 6.2). Fig. 1 Important: If the boiler is installed at a high point in the system it is strongly recommended that Automatic Air Vent Kit 720004701 is fitted. 1.2 Optional Extras Integral timers, RF room thermostats etc. are available as optional extras. 1.3 Contents of Pack...
Page 9
1. With a demand for heating, the pump circulates water through the primary circuit. 2. Once main burner ignites the fan speed controls the gas rate to maintain the heating temperature measured by the temperature sensor. 3. When the flow temperature exceeds the setting temperature, a 3 minute delay occurs before the burner relights automatically (anti cycling). The pump continues to run during this period. 4. When the demand is satisfied the burner is extinguished and the pump continues to run for a period of 3 minutes (Pump Overrun). Central Heating Circuit Fig. 2 Key 1 Primary Heat Exchanger 14 Gas Inlet 2 Burner 15 Domestic Hot Water Outlet 3 Ignition Electrodes 16 Heating Flow 4 Flame Sensing Electrode 17 Pressure Gauge 5 Gas Valve 18 Water Pressure Sensor 6 Pump 20 Fan 7 Automatic Air Vent 21 Diverter Valve Assembly 8 Plate Heat Exchanger/Automatic Bypass 22 Diverter Valve Motor 9 Flow Sensor with Filter & Regulator 23 Domestic Hot Water Flow Temperature Sensor 10 Pressure Relief Valve...
Fig. 3 IMPORTANT: When the selector switch is in the '0' (Off) position the electrical supply to the boiler is isolated. The boiler will not operate and the integral timer will require resetting once the selector switch is set to either Position (i) or Position (ii). 3.3 Frost Protection Mode 1. The frost protection mode is integral to the appliance and functions only with the selector switch (see Section 2.1) in the domestic hot water and central heating position. If the system temperature falls below 5° C then the boiler will fire on its minimum setting until a flow temperature of 30° C is reached. Further protection can be incorporated by using a system frost thermostat. 3.4 Pump Protection 1. With the selector switch (see Section 2.1) in either the central heating or central heating and domestic hot water position, the pump will automatically operate for 1 minute in every 24 hours to prevent sticking. page 9 4.0 Technical Data 4.1 Duotec Combi 24, 28, 33 & 40 HE A Appliance Type Appliance Category CAT I 2H Heat Input CH (Net) 24 model 20.5 28 model 24.7 33 model 28.9 40 model 32.8 Heat Input CH (Gross) 24 model 22.7 28 model 27.4 33 model 32.1 10.8 40 model 36.4 ...
Page 11
40 model Heat Output CH (Condensing) 24 model 28 model 25.9 33 model 30.3 10.2 40 model 34.4 12.1 Heat Input DHW (Net) 24 model 24.7 28 model 28.9 33 model 40 model 41.2 Heat Input DHW (Gross) 24 model 27.4 28 model 32.1 33 model 37.7 ...
Page 12
Overall Height Inc Flue Elbow 965mm Casing Width 450mm Casing Depth 345mm Clearances Above Casing 200 mm Min Below Casing 150 mm Min* Front 450 mm Min (For Servicing) Front 5 mm Min (In Operation) L.H. Side 5 mm Min R.H. Side 5 mm Min (In Operation) *This is MINIMUM recommended dimension. Greater clearance will aid installation and maintenance. Weights (24 model) Packaged Boiler Carton 48.6 kg Installation Lift Weight 43.6 kg (28 model) Packaged Boiler Carton 49.2 kg Installation Lift Weight 44.2 kg (33 & 40 model) Packaged Boiler Carton 51kg Installation Lift Weight 46kg ...
page 10 5.0 Dimensions and Fixings Dimensions A 780mm B 345mm C 450mm D 116mm Ø Min. E 185mm (207mm for 80/125mm flue systems) F 145mm G 131mm H 180mm J 270mm...
6.0 System Details 6.1 Information 1. The Baxi Duotec Combi HE A Condensing Combination Boiler is a 'Water Byelaws Scheme Approved Product'. To comply with the Water Byelaws your attention is drawn to the following installation requirements and notes (IRN). a) IRN 001 See text of entry for installation requirements and notes. b) IRN 302 Byelaw 14. 2. Reference to the WRc publications, 'Water fittings and materials directory' and 'Water supply byelaws guide' give full details of byelaws and the IRNs.
Page 15
6.2 Central Heating Circuit 1. The appliance is suitable for fully pumped SEALED SYSTEMS ONLY. Treatment of Water Circulating Systems All recirculatory water systems will be subject to corrosion unless an appropriate water treatment is applied. This means that the efficiency of the system will deteriorate as corrosion sludge accumulates within the system, risking damage to pump and valves, boiler noise and circulation problems. When fitting new systems flux will be evident within the system, which can lead to damage of system components. All systems must be thoroughly drained and flushed out using, for example, Sentinel X300 or X400 or Fernox F3. They should be used following the flushing agent manufacturer's instructions. System additives corrosion inhibitors and flushing agents/descalers should comply to BS7593 requirements, e.g. Sentinel X100 and Fernox MB1 which should be used following the inhibitor manufacturer's instructions. Full instructions are supplied with the products, for further information contact Sentinel (0800 389 4670) or Fernox (0870 870 0362) Failure to flush and add inhibitor to the system will invalidate the appliance warranty. It is important to check the inhibitor concentration after installation, system modification and at every service in accordance with the manufacturer's instructions. (Test kits are available from inhibitor stockists.) For information or advice regarding any of the above contact Technical Enquiries. 6.3 Bypass 1. The boiler utilises the primary side of the DHW plate heat exchanger as an automatic integral bypass. 6.4 System Control 1. Further external controls (e.g. room thermostat) should be fitted to optimise the economical operation of the boiler. page 12 6.5 System Filling and Pressurising 1. A filling point connection on the central heating return pipework must be provided to facilitate initial filling and pressurising and also any subsequent water loss replacement/refilling. A filling loop & instructions are provided with the boiler 2. The filling method adopted must be in accordance with all relevant water supply regulations and use approved equipment. 3. Your attention is drawn to: for GB: Guidance G24.2 and recommendation R24.2 of the Water Regulations Guide. for IE: the current edition of I.S. 813 "Domestic Gas Installations". 4. The sealed primary circuits may be filled or replenished by means of a temporary connection between the circuit and a supply pipe, provided a 'Listed' double check valve or some other no less effective backflow prevention device is permanently connected at the inlet to the circuit and the temporary connection is removed after use. IMPORTANT: If the boiler is installed at a high point in the system it is strongly recommended that Automatic Air Vent Kit 720004701 is fitted. Fig. 4...
Page 16
Fig. 5 6.6 Expansion Vessel (Central Heating only) 1. The appliance expansion vessel is precharged to 0.5 bar. Therefore, the minimum cold fill pressure is 0.5 bar. The vessel is suitable for correct operation for system capacities up to 125 litres. For greater system capacities an additional expansion vessel must be fitted. For GB refer to BS 7074 Pt 1. For IE, the current edition of I.S. 813 "Domestic Gas Installations". 6.7 Safety Pressure Relief Valve (Fig. 6) 1. The pressure relief valve is set at 3 bar, therefore all pipework, fittings, etc. should be suitable for pressures in excess of 3 bar and temperature in excess of 100°C. 2. The pressure relief discharge pipe should be not less than 15mm dia, run continuously downward, and discharge outside the building, preferably over a drain. It should be routed in such a manner that no hazard occurs to occupants or causes damage to wiring or electrical components. The end of the pipe should terminate facing down and towards the wall. 3. The discharge must not be above a window, entrance or other public access. Consideration must be given to the possibility that boiling water/steam could discharge from the pipe. 4. A remote relief valve kit is available to enable the boiler to be installed in cellars or similar locations below outside ground level (kit no. 5121379). Fig. 6 page 13 6.8 Domestic Hot Water Circuit (Fig. 7) 1. All DHW circuits, connections, fittings, etc. should be fully in accordance with relevant standards and water supply regulations.
2. Your attention is drawn to: for GB: Guidance G17 to G24 and recommendation R17 to R24 of the Water Regulations Guide. for IE: the current edition of I.S. 813 "Domestic Gas Installations". 3. The Water Regulations recommendations for England and Wales prohibits backflow from appliances into the wholesome water supply due to thermal expansion. However this type of instantaneous combination boiler, with less than 15 litres of stored capacity, does not require any backflow prevention device as any thermal expansion is accommodated within the appliance. It is possible in certain circumstances that other cold water demands (e.g. washing machines, flushing of W.C.s) may affect the DHW function of the boiler. In these instances the fitting of a backflow prevention device and expansion vessel is recommended. 4. Also if there is an existing check valve, loose jumpered stop cock, water meter or water treatment device already fitted to the wholesome water supply connected to the boiler domestic hot water (DHW) inlet supply then a suitable expansion device may be required. 5. The boiler's maximum working mains pressure is 8 bar, therefore all pipework, connections, fittings, etc. should be suitable for pressures in excess of 8 bar. A pressure reducing valve must be fitted for pressures in excess of 8 bar. The manufacturer of any outlet fittings, such as a shower valve, may require a lower maximum pressure. The pressure reduction must take account of all fittings connected to the DHW system. Fig. 7 6.9 Showers 1. If a shower control is supplied from the appliance it should be of the thermostatic or pressure balanced type. Thermostatic type shower valves provide the best comfort and guard against water at too high a temperature. Existing controls may not be suitable refer to the shower valve manufacturer. 6.10 Hard Water Areas 1. If the area of the installation is recognised as a HARD WATER AREA then a suitable device should be fitted to treat the mains water supply to the boiler. Contact your Water Distribution Company for advice on suitable devices. page 14 7.0 Site Requirements 7.1 Location 1. The boiler may be fitted to any suitable wall with the flue passing through an outside wall or roof and discharging to atmosphere in a position permitting satisfactory removal of combustion products and providing an adequate air supply. The boiler should be fitted within the building unless otherwise protected by a suitable enclosure i.e. garage or outhouse. (The boiler may be fitted inside a cupboardsee Section 7.3). 2. If the boiler is sited in an unheated enclosure then it is recommended to leave the ON/OFF Selector Switch in the domestic hot water and central heating position to give frost protection. 3. If the boiler is fitted in a room containing a bath or shower reference must be made to the relevant requirements. In GB this is the current I.E.E. Wiring Regulations and Building Regulations. In IE reference should be made to the current edition of I.S. 813 "Domestic Gas Installations" and the current ETCI rules. 4. If the boiler is to be fitted into a building of timber frame construction then reference must be made to the current edition of Institute of Gas Engineers Publication IGE/UP/7 (Gas Installations in Timber Framed Housing). *This is the MINIMUM recommended dimension. Greater clearance will aid installation and maintenance.
Page 18
Fig. 8 Fig. 9 7.2 Clearances (Figs. 8 & 9) 1. A flat vertical area is required for the installation of the boiler.
Page 19
2. These dimensions include the necessary clearances around the boiler for case removal, spanner access and air movement. Additional clearances may be required for the passage of pipes around local obstructions such as joists running parallel to the front face of the boiler. page 15 7.3 Ventilation of Compartments 1. Where the appliance is installed in a cupboard or compartment, no air vents are required. 2. BS 5440: Part 2 refers to room sealed appliances installed in compartments. The appliance will run sufficiently cool without ventilation. 7.4 Gas Supply 1. The gas installation should be in accordance with the relevant standards. In GB this is BS 6891. In IE this is the current edition of I.S. 813 "Domestic Gas Installations". 2. The connection to the appliance is a 22mm copper tail located at the rear of the gas service cock (Fig. 10). 3. Ensure that the pipework from the meter to the appliance is of adequate size, and the demands of any other gas appliances in the property are taken into consideration. Do not use pipes of a smaller diameter than the boiler gas connection (22mm). Fig. 10 7.5 Electrical Supply 1. External wiring must be correctly earthed, polarised and in accordance with relevant regulations/rules. In GB this is the current I.E.E. Wiring Regulations. In IE reference should be made to the current edition of ETCI rules. 2. The mains supply is 230V ~ 50Hz fused at 3A. NOTE: The method of connection to the electricity supply must facilitate complete electrical isolation of the appliance Connection may be via a fused doublepole isolator with a contact separation of at least 3mm in all poles and servicing the boiler and system controls only Fig. A 7.6 Bath & Shower Rooms...
Page 20
1. If the boiler is fitted in a room containing a bath or shower and NOT FITTED with any optional integral timer or thermostat, it can be fitted in zone 2, (Figs. A & B shows zone dimensions for a bathtub. For other examples refer to the Current I.E.E. Wiring Regulations) reference must be made to the relevant requirements. In GB this is the current I.E.E. Wiring Regulations and Building Regulations. In IE reference should be made to the current edition of I.S. 813 "Domestic Gas Installations" and the current ETCI rules. Fig. B page 16 7.7 Condensate Drain FAILURE TO INSTALL THE CONDENSATE DISCHARGE PIPEWORK CORRECTLY WILL AFFECT THE RELIABLE OPERATION OF THE BOILER. CAREFUL CONSIDERATION MUST BE GIVEN TO THE POSSIBILITY OF THE PIPEWORK BEING SUBJECT TO FREEZING CONDITIONS AND APPROPRIATE MEASURES TAKEN TO PREVENT BLOCKAGE. CORRECT INSTALLATION IN ACCORDANCE WITH THIS SECTION WILL CONSIDERABLY MINIMISE THE LIKELIHOOD OF BLOCKAGE AND SUBSEQUENT BOILER LOCKOUT. A CONDENSATE DISCHARGE PUMP AND PIPE 'TRACE HEATING' ARE AVAILABLE AS ACCESSORIES see paragraphs 7.7.12 to 7.715 for further details. The condensate discharge pipe MUST NOT RISE at any point along its length. There MUST be a fall of AT LEAST 2.5° (50mm per metre) along the entire run EXCEPT when employing a suitable condensate pump in basement and cellar or similar applications. The boiler condensate trap incorporates a seal of 75mm, therefore it is unnecessary to install an air break and trap in the discharge pipework. 1. The condensate outlet will accept 21.5mm (3/4in) plastic overflow pipe. It is strongly recommended that this discharges internally into the household drainage system. Where this is not possible, discharge into an outside drain is permissible providing every possible precaution is taken to prevent freezing. 2. Ensure the discharge of condensate complies with any national or local regulations in force. BS 6798 & Part H1 of the Building Regulations give further detailed guidance. 3. The discharge pipe should be run in a proprietary drain pipe material e.g. PVC, PVCU, ABS, PVCC or PP. 4. Metal pipework is NOT suitable for use in condensate discharge systems. 5. The pipe should be a minimum of 21.5mm diameter and must be supported using suitably spaced clips of the correct design to prevent sagging. 6. It is advisable that the full length of condensate pipe is run internally and preferably be less than 3 metres. 7. Internal runs greater than 3 metres or runs in cold areas should use 32mm waste pipe. 8. External runs MUST be a MINIMUM of 32mm and fully insulated with material suitable for external use. 9. If the boiler is fitted in an unheated location the entire condensate discharge pipe should be treated as an external run and sized and insulated accordingly. 10. In all cases discharge pipe must be installed to aid disposal of the condensate. To reduce the risk of condensate being trapped, as few bends and fittings as possible should be used and any burrs on cut pipe removed. Examples are shown of the following methods of termination: i) to an internal soil & vent pipe ii) via an internal discharge branch (e.g. sink waste) downstream of the trap iii) to a drain or gully iv) to a purpose made soakaway...
Page 21
v) pumped into an internal discharge branch (e.g. sink waste) downstream of the trap vi) pumped into an external soil & vent pipe vii) to a drain or gully with extended external run & trace heating It is strongly recommended to discharge internally into the household drainage system. If connecting to a rain water drain, that drain MUST discharge into a foul drain. i) Termination to an internal soil and vent pipe ii) External termination via internal discharge branch e.g sink waste downstream* page 17 11. When discharging condensate into a soil stack or waste pipe the effects of existing plumbing must be considered. If soil pipes or waste pipes are subjected to internal pressure fluctuations when WC's are flushed or sinks emptied then back pressure may force water out of the boiler trap and cause appliance lockout. iii) Termination to a drain or gully...
Page 22
iv) Termination to a purpose made soakaway page 18 12. A boiler discharge pump is available, 'MULTIFIT' part no. 720648301. This pump will dispose of both condensate & high temperature water from the relief valve. It has a maximum head of 5 metres. Follow the instructions supplied with the pump. 13. Condensate Drain Pipe 'Trace Heating' Elements are available in various lengths. 'MULTIFIT' part nos.: 1 metre 720644401 2 metre 720664101 3 metre 720664201 5 metre 720664401* * Where the drain is between 3 & 5 metres a 5 metre kit can be used and "doubled back" upon itself. 14. It is possible to fit the element externally on the condensate drain or internally as detailed in the instructions provided. 15. The fitting of a 'Trace Heating' Element is NOT a substitute for correct installation of the condensate drain. ALL requirements in this section must still be adhered to. v) pumped into an internal discharge branch (e.g. sink waste) downstream of the trap...
Page 23
vi) pumped into an external soil & vent pipe vii) to a drain or gully with extended external run & trace heating...
Page 24
page 19 7.8 Flue NOTE: Due to the nature of the boiler a plume of water vapour will be discharged from the flue. This should be taken into account when siting the flue terminal. 1. The following guidelines indicate the general requirements for siting balanced flue terminals. For GB recommendations are given in BS 5440 Pt 1. For IE recommendations are given in the current edition of I.S. 813 "Domestic Gas Installations". 2. If the terminal discharges onto a pathway or passageway, check that combustion products will not cause a nuisance and that the terminal will not obstruct the passageway. 3. If a terminal is less than 2 metres above a balcony, above ground or above a flat roof to which people have access, then a suitable terminal guard must be provided. 4. * Reduction to the boundary is possible down to 25mm but the flue deflector kit (part no. 5111068) must be fitted. IMPORTANT: Under car ports we recommend the use of the plume displacement kit. The terminal position must ensure the safe and nuisance free dispersal of combustion products. Terminal Position with Minimum Distance (Fig. 12) (mm) Directly below an opening, air brick, opening windows, etc. Above an opening, air brick, opening window etc. Horizontally to an opening, air brick, opening window etc. Below gutters, soil pipes or drain pipes. 25 (75) Below eaves. 25 (200) Below balconies or car port roof. 25 (200) From a vertical drain pipe or soil pipe. 25 (150) From an internal or external corner. 25 (300) Above ground, roof or balcony level. From a surface or boundary line facing a terminal. K From a terminal facing a terminal (Horizontal flue). 1200 From a terminal facing a terminal (Vertical flue). From an opening in carport (e.g. door, window) into the dwelling. 1200 M Vertically from a terminal on the same wall. 1500 N Horizontally from a terminal on the same wall.
Page 25
In addition, the terminal should be no nearer than 150 mm to an opening in the building fabric formed for the purpose of accommodating a builtin element such as a window frame. Only ONE 25mm clearance is allowed per installation. If one of the dimensions D, E, F, G or H is 25mm then the remainder MUST be as shown in brackets, in accordance with B.S.54401. NOTE: The distance from a fanned draught appliance terminal installed parallel to a boundary may not be less than 300mm in accordance with the diagram below Fig. 11 Fig. 12 IMPORTANT: If fitting a Plume Displacement Flue Kit, the air inlet must be a minimum of 150mm from any opening windows or doors (see Section 9.0).
Fig. 12a page 20 8.0 Flue Options 8.1 Horizontal Flue Systems 1. The standard flue is suitable only for horizontal termination applications. 2. All fittings should be fully engaged. The approximate engagement is 40mm. Apply soap solution to the seal on each fitting to aid assembly. 3. Maximum permissible equivalent flue lengths are: (60/100) (80/125) Horizontal Concentric 10 metres 20 metres 4. Any additional "in line" bends in the flue system must be taken into consideration. Their equivalent lengths are: Concentric Pipes: 135° bend 0.5 metres 93° bend 1.0 metres The elbow supplied with the standard horizontal telescopic flue kit is not included in any equivalent length calculations NOTE: Flue length is measured from point X to Y as shown. IMPORTANT: All flue systems must be securely supported at least once every metre. Suitable pipe supports are available as accessories. Horizontal Flues...
Page 27
NOTE: Horizontal flue pipes should always be installed with a fall of at least 1.5° from the terminal to allow condensate to run back to the boiler. page 21 8.2 Twin & Vertical Flue Systems 1. Maximum permissible equivalent flue lengths are: (60/100) (80/125) Vertical Concentric 10 metres 20 metres Vertical Twin Pipe 15 metres 2. Any additional "in line" bends in the flue system must be taken into consideration. Their equivalent lengths are: Concentric Pipes: 0.5 metres 135° bend 93° bend 1.0 metres Twin Flue Pipe 135° bend 0.25 metres...
Page 28
91.5° bend 0.50 metres The elbow supplied with the standard horizontal telescopic flue kit is not included in any equivalent length calculations NOTE: Flue length is measured from point X to Y as shown. Vertical Fluess IMPORTANT: All flue systems must be securely supported at least once every metre. Suitable pipe supports are available as accessories. For terminal position see literature provided with kit Vertical Flues (Twin Pipe) ...
Page 29
Total Equivalent Length = A+B+C+1x90° Bend All vertical and angled runs must be included, measured from the boiler adaptor (point X) to the joint with the flue terminal (point Y). One 91.5° bend or two 135° bends can be included without reduction of the flue length. If further elbows are required the flue length must be reduced by the following amounts: The total equivalent length for this example is = 6.5 metres. AIR DUCT Equivalent No of Sub total Length fittings/pipes Value 1m extension 5.0m 135°bend 0.25m 0.5m 91.5°bend 0.5m 1.0m Equivalent Length Air Duct = 6.5m FLUE DUCT Equivalent No of Sub total Length Value fittings/pipes 1m extension 5.0m 135°bend 0.25m 0.5m 91.5°bend 0.5m 1.0m...
Page 30
Flue Extension 1000mm 5111074 Flue Bend 93° 5111075 Flue Bend (pair) 135° 5111085 Pipe Support (painted) 100mmØ 5111080 Vertical Flue Adaptor 5111070 Wall Liner 5111067 Flue Terminal Deflector 5111068 FLUE GROUP N Twin Flue System 80mm diameter Flue Extension (pair) 1000mm 5111087 Flue Bend (pair) 90° 5111072 Flue Bend (2 pair) 135° 5111086 Vertical Flue Boiler Adaptor Kit 720089801 Vertical Flue Adaptor ...
Page 31
page 23 8.4 Twin Flue Duct Adaptor 1. The kit allows connection of a twin flue system to the boiler adaptor. 8.5 Twin Flue Connection 1. Engage the twin flue duct adaptor in the boiler adaptor, making sure that it is pushed down as far as possible. 2. Ensure that the air & flue ducts are connected correctly and that they are adequately supported (at least once every metre using the available pipe supports). 3. Ensure that all joints and elbows are fully engaged and cannot become disconnected during operation.
Page 32
page 24 8.6 For Roof Terminals 1. In the case of a pitched roof 25 50 degrees, position the lead tile to replace/flash over existing roof tiling. Make an aperture in the roof suitable for the lower tube of the roof terminal and ensure the integrity of the roof cover is maintained. The adjustable plastic collar can either be positioned on the lead tile or the lower tube of the roof terminal prior to the final positioning of the vertical flue through the tile. Check the collar is correctly located to suit required roof pitch (either 25° to 38° or 37° to 50°). From inside the roof adjust the flue to a vertical position and secure to the roof structure with the clamp supplied. 2. For flat roof installations the aluminium flashing must be incorporated into the roof covering and the appropriate aperture made in the roof decking. The vertical flue is lowered onto the flashing making sure the collar of the flue locates securely with the flashing. (A mastic seal may be necessary). From inside the roof, adjust the flue to a vertical position and secure to the roof structure with the clamp supplied. IMPORTANT: If the boiler is not fitted immediately after the flue system, temporary precautions must be taken to prevent rain entry into the room of installation. Any precautionary measures must be removed prior to commissioning the boiler.
Page 33
8.7 Flue Dimensions The standard horizontal telescopic flue kit allows for lengths between 315mm and 500mm from elbow to terminal (Fig. 13). The maximum permissible equivalent flue length is: 10 metres (60/100 system) 20 metres (80/125 system) 8.8 Flue Trim 1. The rubber flue trim supplied may be fitted to either the outside wall or on the inner wall of installation. Fig. 13 8.9 Terminal Guard (Fig. 14) 1. When codes of practice dictate the use of terminal guards, they can be obtained from most Plumbers' and Builders' Merchants. 2. There must be a clearance of at least 50mm between any part of the terminal and the guard. 3. When ordering a terminal guard, quote the appliance name and model number. 4. The flue terminal guard should be positioned centrally over the terminal and fixed as illustrated. Fig. 14 8.10 Flue Deflector...
1. If required, push the flue deflector over the terminal end and rotate to the optimum angle for deflecting plume. Secure the deflector to the terminal with screws provided. page 25 9.0 Plume Displacement 9.1 Plume Displacement Kit (Fig. 14b) Kit No 5118638 Content of kit 1 0.9m 60/100 Concentric Flue 1 1m 60 Dia Exhaust Flue Pipe 1 Adaptor 2 60 Dia Support Brackets 1 93° Elbow/Plume Outlet Assembly 1 Flexible Flue Trim 3 "O" Rings 1 'Jubilee Clip 1 Elbow 1. This kit is recommended for installations where the condensate plume emitted from the flue may cause a nuisance or affect the surroundings. 2. The terminal must be positioned outside the building with the air inlet facing downward and outlet connection upwards. 3. The plume outlet must always be at least 45° to the wall, with the 'peak' uppermost to prevent rain entry (Figs. 15 & 16), and be at least 2 metres above ground level. It must be secured as shown in Fig. 12a. The plume outlet must also be at least 500mm from the air inlet in any direction (Fig. 16). NOTE: The outlet must be positioned so that any condensate plume is directed away from adjacent surfaces. There must be a constant fall along the entire length of the flue system from the outlet back to the boiler. 4. It is possible to reduce or increase (with the addition of extensions) the length of either or both the 60/100 concentric and 60Ø exhaust. 5. Standard concentric flue extension kits may be added between the boiler elbow and the terminal assembly. 6. The minimum length of the concentric flue is 100mm when measured from the edge of the flue elbow. IMPORTANT: The maximum equivalent length of concentric flue is: 8 metres Additional bends may be fitted in the concentric flue, but the equivalent length ...
Page 35
Fig. 14b Fig. 15 & Fig. 16 page 26 9.2 Determining Permissible Lengths In the graph the solid line diagonal represents the relationship between the concentric flue assembly (and any extensions) and the 60Ø exhaust (and any extensions or additional bends).
Page 36
Example 1 Not Permissible If, for instance, a concentric length of 5 metres was required and the 60Ø exhaust needed to be 6 metres the graph shows that this combination would NOT be permissible as the intersection point would be above the solid diagonal line. Example 2 Flue Lengths OK Where both lengths have been determined they can be applied to the graph to check that the installation is permissible. For example, if it was known that 2 metres of concentric flue and 4 metres of 60Ø exhaust were required, the values could be applied to the graph as shown in Example 2. As the point of intersection of the dotted lines is below the solid diagonal line, the combination of lengths is shown to be acceptable. Example 3 Flue Lengths OK In the example shown, assume that the concentric part of the flue needs to be 2.3 metres long. Find the position of '2.3' on the horizontal axis of the graph and then project upwards to the solid diagonal line. This is represented by the vertical thick dotted line. Where this dotted line intersects with the solid diagonal line on the graph, project across to the vertical axis. As can be seen this corresponds with 6 metres. Therefore, the total equivalent length of the 60Ø exhaust can be up to 6 metres. Any elbow equivalencies must be accounted for i.e. 93° elbows are equal to 1 metre, each 45° elbow to 0.5 metres. Example 1 Flue Lengths Not Permissible Example 2 Flue Lengths OK Example 3 Flue Lengths OK...
Page 37
Fig. 17 Fig. 18 Additional Accessories 93° Elbow 5121369 45° Elbow (Pair) 5121370 1 metre 60Ø Extension 5121368 Flue Length Worked Example Baxi Duotec Combi 28 HE In Fig. 18 Above an additional 93° elbow and pair of 45° elbows have been included in the 60Ø exhaust. Also 3 straight extension pieces have been used. To calculate total length: Length of 60Ø supplied in kit = 1 metre 3 x 1 metre Extensions = 3 metres 1 x 93° Elbow = 1 metre 2 x 45° Elbow = 1 metre (0.5 metres each) Total 60Ø = 6 metres...
Page 38
After consulting the table in Example 3 it can be determined that the concentric flue could be up to approximately 2.3 metres long. page 27 9.3 General Fitting Notes 1. Cut a hole in the external wall which the concentric flue assembly will pass through. The hole should allow the flue to fall back to the boiler at an angle of 1.5° to 3°. 2. When completed the terminal must be at least 2 metres above ground level (Fig. 19). 3. Measure and cut to size the concentric assembly and any extensions that are being used. 4. Insert the concentric assembly through the hole from outside the building. 5. If required, the flexible flue trim should be fitted prior to this as it cannot be fitted after. Use the large 'Jubilee' clip to secure the trim to the flue (See Fig. 20, trim shown dotted), with the screw part of the clip at the bottom. 6. Connect any extensions or elbows that are being used to the concentric assembly. Engage the extension, elbow or concentric assembly in the boiler flue elbow. Fit the boiler flue elbow to the boiler adaptor. 7. Ensure that the concentric assembly and any extensions fall back to the boiler at an angle of 3° and that the external air inlet is to the bottom. 8. Use suitable brackets to support the concentric assembly and any extensions, and make good inside and outside. 9. The 60Ø exhaust can now be fitted. Slide the adaptor over the plain end of the 60Øexhaust (Fig. 22) and engage the exhaust in the terminal. Slide the adaptor down over the spigot. Mark and drill the adaptor, using a 2mm bit, as shown in Fig. 21. Secure the adaptor to the spigot using one of the screws supplied. 10. If it is necessary to shorten the 60Ø exhaust or any of the extensions, the excess material must be cut from the plain end of the pipe. 11. Determine the position of the 60Ø exhaust and mark on the wall a suitable position for the support bracket. If extensions are being used, a support bracket is supplied in each kit. 12. Drill the wall, and fit the bracket(s) using the plug and screw provided. 13. Mark and drill the 60Ø exhaust, using a 2mm bit, as shown in Fig. 23. Complete the installation of the 60Ø exhaust, securing in the brackets. 14. Fit the 93° elbow/plume outlet and secure with the two remaining screws supplied. Ensure the plume outlet is at least 45° to the wall and that the 'peak' is uppermost (Fig. 24). Fig. 19...
Page 39
Fig. 20 Fig. 21 Fig. 22 Fig. 23 Fig. 24 page 28 15. For aesthetic purposes it is permissible to route the 60Ø exhaust in an enclosed box, but the air inlet and plume outlet MUST remain in free air. 16. It is also possible to separate the plume outlet from the 93° elbow to allow the flue to be installed as shown in Fig. 25. 17. To do this, first slacken the two screws retaining the plume outlet to the elbow, and remove the outlet (Fig. 26). The elbow can now be used to connect the vertical to horizontal 60Ø exhaust (Fig. 25). Retighten the screws in the elbow. 18. The outlet can now be fitted into the female end of an 60Ø extension piece. It must be secured using two of the screws supplied in the bag with the 'Jubilee' clip. 19. Mark the female end of the extension at 30mm as shown in two positions, directly opposite each other (Fig. 27). 20. Using a suitable bit (e.g. 2mm), drill through the extension and outlet. Secure using two of the screws supplied. 21. The remaining screw must be used to secure the adaptor to the concentric terminal. 22. When the plume outlet is positioned under a balcony or other projection (Fig. 28) it must protrude at least 200mm (it is not necessary to extend it further than this). 23. When under balconies or projections it is permissible to rotate the concentric flue length up to 70°, clockwise or anticlockwise (Fig. 29), if there is insufficient space to connect vertically. 24. This will allow the connection of the exhaust to the outlet spigot. 25. All other minimum & maximum dimensions must be adhered to, and the air inlet positioned such that it will not be subject to rain entry.
10.0 Installation 10.1 Unpacking & Initial Preparation The gas supply, gas type and pressure must be checked for suitability before connection (see Section 7.4). NOTE: a small amount of water may drain from the boiler in the upright position. 1. Remove staples, open flaps and remove the cardboard sheet. Remove the polystyrene side pieces and literature. Two people can then lift out the boiler (Figs. 30 & 31). 2. After considering the site requirements (see Section 7.0) position the fixing template on the wall ensuring it is level both horizontally and vertically. 3. Mark the position of the two most suitable fixing slots for the wall plate and boiler lower fixing holes. It is preferable to use the vertical fixing slots. 4. Mark the position of the centre of the flue hole (rear exit). For side flue exit, mark as shown (Fig. 32). 5. If required, mark the position of the gas and water pipes. Remove the template. 6. Cut the hole for the flue (minimum diameter 116mm). 7. Drill the wall as previously marked to accept the wall plugs supplied. Secure the wall plate using the fixing screws. 8. Using a spirit level ensure that the plate is level before finally tightening the screws. 9. Connect the gas and water pipes to the valves on the wall plate using the copper tails supplied. Ensure that the sealing washers are fitted between the connections. IMPORTANT: ONLY on 40 models the Cold Water Inlet tap is fitted with a flow regulator. The copper tail is factory fitted on this model, but must be loosened and turned through 180° to point downwards. Ensure the joint is fully tight (Fig. 33). 10. Fit the filling loop as described in the instructions supplied with it. Fig. 30 Fig. 31 Fig. 32...
Page 42
Fig. 33 Fig. 34 10.2 Flushing 1. Connect a tube to the central heating flow or return pipe (Fig. 34). 2. Flush thoroughly (see System Details, Section 6.2). page 30 10.3 Fitting The Boiler 1. Remove the sealing caps from the boiler connections. NOTE: A small amount of water may drain from the boiler once the caps are removed. 2. Lift the boiler as indicated by the shaded areas. The boiler should be lifted by TWO PEOPLE. Engage the slots at the top rear of the boiler on the wall plate (Fig. 35) (see Safe Manual Handling). 3. Insert the sealing washers between the valves and pipes on the wall plate and the boiler connections. The rubber washers must be used on the gas connection. 4. Tighten all the connections. Fig. 35 10.4 Fitting the Safety Pressure Relief Discharge Pipe (Fig. 36) 1. Remove the discharge pipe from the kit. 2. Determine the routing of the discharge pipe in the vicinity of the boiler. Make up as much of the pipework as is practical, including the discharge pipe supplied. 3. The pipework must be at least 15mm diameter and run continuously downwards to a discharge point outside the building. See section 6.7 for further details. 4. Utilising one of the sealing washers, connect the discharge pipe to the adaptor and tighten the nut. 5. Complete the discharge pipework and route it to the outside discharge point.
Page 43
IMPORTANT: Make all soldered joints before connecting to the pressure relief valve. Fig. 36 10.5 Condensate Drain (see section 7.7) 1. Connect the condensate drain to the trap outlet pipe. Ensure the discharge of condensate complies with any national or local regulations in force (see British Gas "Guidance Notes for the Installation of Domestic Gas Condensing Boilers". 2. The connection will accept 21.5mm (3/4in) plastic overflow pipe which should generally discharge internally into the household drainage system. If this is not possible, discharge into an outside drain is acceptable. page 31 10.6 Fitting The Flue HORIZONTAL TELESCOPIC FLUE 1. There are two telescopic sections, the Terminal Assembly and the Connection Assembly, a roll of sealing tape and two self tapping screws. A 93° elbow is also supplied. The outer duct of the Connection Assembly is painted white. On the Terminal Assembly the outer duct is unpainted. 2. The two sections can be adjusted to provide a length between 315mm and 500mm (Fig. 37) when measured from the flue elbow (there is 50mm engagement into the elbow). 3. Locate the flue elbow on the adaptor at the top of the boiler. Set the elbow to the required orientation (Fig. 39). NOTE: The flue elbow is angled at 93 degrees to ensure a fall back to the boiler. 4. Measure the distance from the outside wall face to the elbow. This dimension will be known as 'X' (Fig. 38). 5. If the distance from the flue elbow to the outside face of the wall ('X' in Fig. 38) is less than 250mm the Connection Assembly can be discarded and the Terminal Assembly fitted directly into the elbow. 6. In instances where the dimension 'X' (Fig. 38) is between 250mm and 315mm it will be necessary to shorten the Terminal Assembly by careful cutting to accommodate walls of these thicknesses. 7. To dimension 'X' add 50mm. This dimension to be known as 'Y'.
Page 45
Fig. 39 page 32 8. Adjust the two telescopic sections to dimension 'Y' (Fig. 41). Ensure that the rivets and holes in the Connection Assembly are aligned horizontally (Fig. 42). 9. Using a 2mm bit, drill through the holes at the end of the Connection Assembly into the Terminal Assembly and secure them together using the screws supplied (Fig. 41). Seal the joint with the tape provided (Fig. 43). 10. Remove the flue elbow and insert the flue through the hole in the wall. Refit the elbow to the boiler adaptor, ensuring that it is pushed fully in (Fig. 43). 11. Draw the flue back through the wall and engage it in the elbow. It may be necessary to use soap solution or similar to ease assembly of the elbow adaptor and flue (Fig. 43). 12. Ensure that the terminal is positioned with the slots to the bottom (Fig. 44). IMPORTANT: It is essential that the flue terminal is fitted as shown to ensure correct boiler operation and prevent water entering the flue. 13. Make good between the wall and air duct outside the building. 14. Fit the flue trim if required, and if necessary fit a terminal guard (see Section 8.8 & 8.9). CONCENTRIC VERTICAL FLUE 15. Once the length of the vertical concentric extension has been determined mark and carefully cut off the excess material. The cut end MUST be square and free of burrs to ensure correct insertion into the boiler adaptor. 16. Measure 25mm from the end of the flue extension and apply a length of tape around the outer duct (Fig. 45). 17. Engage the extension into the adaptor up to this position (Fig. 46). Once the installation of the flue is complete and all support brackets are securely in place remove the tape. Fig. 41...
Page 47
Fig. 46 page 33 10.7 Making The Electrical Connections The boiler is fitted with a 1.3m length of 3 core cable. This can be connected to the fused 3A 230V 50HZ supply. NOTE: Both the Live and Neutral connections are fused. To connect an external control proceed as follows: 1. Slacken the facia panel securing screws and lift the outercase panel so that its securing tabs are clear of the facia. Remove the panel. 2. Completely undo the screws securing the facia panel and hinge it down (Fig. 47). 3. Undo the terminal block cover securing screw and remove the cover (Fig. 47). 4. Slacken the unused cable clamp on the LH side of the boiler chassis (Fig. 48). Insert the external control wiring through the clamp and route it to the terminal block. 5. Refer to the instructions supplied with the control. IMPORTANT: The room thermostat MUST be suitable for 230V switching. NOTE: An external frost thermostat cannot be used with the optional integral timer. 6. Remove the link between terminals 1 & 2. The 230V supply at terminal 2 must be connected to the thermostat. The switched output from the thermostat must be connected to terminal 1. (Figs. 49 & 50). If the room thermostat being used incorporates an anticipator it MUST be wired as shown in Figs. 49 & 50. 7. Ensure that the external control input cable(s) have sufficient slack to allow the control box to drop down. Tighten the cable clamp on the boiler chassis. 8. Replace the terminal block cover, routing the external control input cable(s) through the second cutout.
Fig. 48 and Fig. 47 Fig. 49 Fig. 50 NOTE: The 230V switched signal for external controls (Frost Stat Room Stat Timer) must always be taken from terminal 2 at the boiler. Live, Neutral and Earth to power these controls must be taken from the Fused Spur. 10.9 Preliminary Electrical Checks 1. Prior to commissioning the boiler preliminary electrical system checks should be carried out. 2. These should be performed using a suitable meter, and include checks for Earth Continuity, Resistance to Earth, Short Circuit and Polarity. page 34 11.0 Commissioning 11.1 Commissioning the Boiler 1. Reference should be made to BS:EN 12828 & 14336 when commissioning the boiler. 2. At the time of commissioning, complete all relevant sections of the Benchmark Checklist at the rear of this publications. 3. Open the mains water supply to the boiler. 4. Open all hot water taps to purge the DHW system. 5. Ensure that the filling loop is connected and open, then open the heating flow and return valves on the boiler. 6. Open the screw on the automatic air vent on the pump body (Fig. 52). 7. The system must be flushed in accordance with BS 7593 (see Section 6.2) and the flushing agent manufacturers instructions. 8. Pressurise the system to 1.5 bar then close and disconnect the filling loop. 9. Turn the gas supply on and purge according to in GB BS 6891 and in IE I.S. 813 "Domestic Gas Installations". 10. Test for gas tightness. 11. Hinge the facia panel upwards and refit the case front panel. Tighten the securing screws. IMPORTANT: The combustion for this appliance has been checked, adjusted and preset at the factory for operation on the gas type specified on the appliance data plate. No measurement of the combustion is necessary. Do not adjust the air/gas ratio valve. 12. Having checked:...
Page 49
That the boiler has been installed in accordance with these instructions. The integrity of the flue system and the flue seals. The integrity of the boiler combustion circuit and the relevant seals. Proceed to put the boiler into operation as follows: Fig. 52, Fig. 53 and Fig. 54 page 35 11.2 Check the Operational (Working) Gas Inlet Pressure 1. Ensure that all controls are calling for heat, and the selector switch is in the central heating and hot water position ( The current boiler temperature is shown on the display. 2. To check the gas rate it is necessary to set the boiler to 'Calibration Mode'. 3. Turn both temperature control knobs fully anticlockwise, then quickly turn the DHW temperature knob 1/4 clockwise twice and back fully anticlockwise (Fig. 55). 4. The display will now alternate between 'SF' and the current boiler temperature and both green LEDs will flash (Figs. 56 & 57). 5. Turn CH temperature control knob fully clockwise. As the knob is turned the display will change from '0' to '00' (Fig. 58) indicating maximum rate, then revert to 'P' alternating with the current boiler temperature (Figs 59 & 60). 6. With the boiler operating in the maximum rate condition check that the operational (working) gas pressure at the inlet gas pressure test point (Fig. 55a) is in accordance with B.S. 6798 & B.S. 6891. 7. Ensure that this inlet pressure can be obtained with all other gas appliances in the property working. Measure the Gas Rate 8. With any other appliances & pilot lights turned OFF the gas rate can be measured. It should be between: 24 model 2.61 m3/h...
Page 50
28 model 3.1 m3/h 33 model 3.6 m3/h 40 model 4.36 m3/h 9. The 'Calibration Function' is active for 20 minutes unless the maximum CH temperature is exceeded. 10. The function can be disabled at any time by turning the DHW temperature knob. 11. Carefully read and complete all sections of the Benchmark Commissioning Checklist at the rear of this publication that are relevant to the boiler and installation. These details will be required in the event of any warranty work. The publication must be handed to the user for safe keeping and each subsequent regular service visit recorded. 12. For IE, it is necessary to complete a "Declaration of Conformity" to indicate compliance with I.S. 813. An example of this is given in I.S. 813 "Domestic Gas Installations". This is in addition to the Benchmark Commissioning Checklist. Fig. 55 Fig. 55a Fig. 57 Fig. 56...
Fig. 58 Fig. 59 Fig. 60 page 36 12.0 Completion 12.1 Completion 1. Instruct the user in the operation of the boiler and system, explaining the operational sequence. 2. Set the central heating and hot water temperature control knobs to the requirements of the user. 3. Carefully read and complete all sections of the Benchmark Commissioning Checklist at the rear of this publication that are relevant to the appliance and installation. These details will be required in the event of any warranty work. The publication must be handed to the user for safe keeping and each subsequent regular service visit recorded. 4. For IE, it is necessary to complete a "Declaration of Conformity" to indicate compliance with I.S. 813. An example of this is given in I.S. 813 "Domestic Gas Installations". This is in addition to the Benchmark Commissioning Checklist. 5. Hand over the Users Operating, Installation and Servicing Instructions giving advice on the necessity of regular servicing. Fig. 61...
page 37 13.0 Servicing 13.1 Annual Servicing 1. For reasons of safety and economy, it is recommended that the boiler is serviced annually. Servicing must be performed by a competent person in accordance with B.S. 79674. 2. After servicing, complete the relevant Service Interval Record section of the Benchmark Commissioning Checklist at the rear of this publication. IMPORTANT: During routine servicing, and after any maintenance or change of part of the combustion circuit, the following must be checked: The integrity of the complete flue system and the flue seals. The integrity of the boiler combustion circuit and relevant seals as described in Section 13.2. The operational gas inlet pressure as described in Section 11.2. 1 to 7 and the gas rate as described in 11.2. 8. The combustion performance as described in 'Check the Combustion Performance' (13.1.4 to 13.1.6 below). 3. Competence to carry out Checking Combustion Performance B.S. 6798 'Specification for Installation & Maintenance of Gas Fired Boilers not exceeding 70kW' advises that: The person carrying out a combustion measurement should have been assessed as competent in the use of a flue gas analyser and the interpretation of the results. The flue gas analyser used should be one meeting the requirements of BS7927 or BSEN503793 and be calibrated in accordance with the analyser manufacturers' requirements. Competence can be demonstrated by satisfactory completion of the CPA1 ACS assessment, which covers the use of electronic portable combustion gas analysers in accordance with BS 7967, Parts 1 to 4. Check the Combustion Performance (CO/CO2 ratio) 4. Set the boiler to operate at maximum rate as described in Section 15.1.1 to 15.1.6. 5. Remove the plug from the flue sampling point, insert the analyser probe and obtain the CO/CO ratio. This must be less than 0.004. 6. If the combustion reading (CO/CO ratio) is greater than this, and the integrity of the complete flue system and combustion circuit seals has been verified, and the inlet gas pressure and gas rate are satisfactory either: Perform the 'Annual Servicing Inspection' (Section 13.2) & recheck Adjust the gas valve (Section 15.0) & recheck Replace the gas valve (Section 14.23) & recheck...
Page 53
Fig. 62 Fig. 63 and Fig. 64 13.2 Annual Servicing Inspection 1. Ensure that the boiler is cool. 2. Ensure that both the gas and electrical supplies to the boiler are isolated. 3. Slacken the screws securing the facia panel. Lift the outercase panel so that its securing tabs are clear of the facia. Remove the panel, allowing the facia to hinge down (Fig. 62). 4. Remove the screws securing the inner door panel. Lift the panel slightly to disengage it from the studs on top of the case (Fig. 63). 5. Unscrew the sump from the bottom of the condensate trap assembly (Fig. 64) and remove any deposits from the sump and trap. Clean as necessary and replace the sump. page 38 6. Undo the nut on the gas inlet pipe to the venturi (Fig. 65) and pull the sensing pipe off the fan. 7. Disconnect the electrode leads, noting their position, and the fan electrical plugs (Fig. 66). 8. Undo the four nuts retaining the combustion box cover to the heat exchanger. 9. Carefully draw the fan, collector and cover assembly forward, being careful to retain the injector in the venturi (Figs. 65 & 66). 10. Clean any debris from the heat exchanger and check that the gaps between the tubes are clear. 11. Inspect the burner, electrodes position and insulation, cleaning or replacing if necessary. Clean any dirt or dust from the air box. 12. Reassemble in reverse order. NOTE: The sensing pipe must be reconnected to the fan, not the venturi. DHW Filter (Fig. 68) 13. If the flow of domestic hot water is diminished, it may be necessary to clean the filter. 14. Initially check the cold water inlet tap filter. 15. Turn the tap off and draw off from a hot tap. Undo the blanking cap and remove the threaded bush (Fig. 67). 16. Extract the filter and rinse thoroughly in clean water. Reassemble and check the flow. If required clean the restrictor filter as described below. 17. Pull off the hall effect sensor. Undo the restrictor from the inlet/return manifold. 18. Rinse the filter thoroughly in clean water and reassemble in reverse order. 19. Turn the selector switch fully anticlockwise against the spring pressure to the reset position and hold for 5 seconds to reset the boiler.
Page 54
20. Complete the relevant Service Interval Record section of the Benchmark Commissioning Checklist at the rear of this publication and then hand it back to the user. Electrode Position...
Fig. 65, Fig. 66, Fig. 67 and Fig. 68 page 39 14.0 Changing Components IMPORTANT: When changing components ensure that both the gas and electrical supplies to the boiler are isolated before any work is started. When the component has been changed turn the selector switch fully anticlockwise against the spring pressure to the reset position and hold for 5 seconds to reset the boiler before recommissioning. See Section 13.2 "Annual Servicing" for removal of case panel, door etc. 14.1 Igniter (Fig. 69) 1. Disconnect the igniter feed plug and the electrode leads, noting their positions. 2. Undo the screw securing the bracket to the boiler. 3. Remove the igniter and transfer the bracket to the new component. 4. Reassemble in reverse order. 14.2 Spark and Sensing Electrodes (Fig. 70) 1. Disconnect the electrode leads, noting their positions. 2. Remove the retaining screws securing each of the electrodes to the combustion box cover and remove the electrodes. 3. Check the condition of the sealing gaskets and replace if necessary. Reassemble in reverse order.
Page 56
Fig. 69 and Fig. 70 page 40 14.3 Fan (Fig. 71) 1. Undo the nut on the gas inlet pipe to the venturi (Fig. 49) and pull the sensing pipe off the fan. 2. Disconnect the electrode leads, noting their position and disconnect the fan electrical plugs. 3. Undo the screws securing the collector to the extension piece. 4. Remove the collector and fan assembly, being careful to retain the injector in the venturi. 5. Undo the screws securing the fan to the venturi and fit the new fan, replacing the seal if necessary.
Page 57
6. Examine the burner gasket and replace if necessary. 7. Reassemble in reverse order, ensuring that the injector is in place and the sensing pipe is connected to the fan. Fig. 72 Fig. 71...
Page 58
Fig. 73 14.4 Venturi (Fig. 71) 1. Remove the collector and fan assembly as described in section 14.3. 2. Extract the injector from the venturi. 3. Undo the screws securing the fan to the venturi and the venturi to the collector. IMPORTANT: When fitting the new venturi, ensure the arrows on it's base point into the collector (Fig. 73). 4. Examine the seals and burner gasket, replace if necessary. 5. Reassemble in reverse order, ensuring that the injector is in place. 14.5 Injector (Fig. 71) 1. Remove the collector and fan assembly as described in section 14.3. 2. Extract and replace the injector and reassemble in reverse order. page 41 14.6 Burner (Fig. 74) 1. Undo the screws securing the collector to the venturi and extension piece. Remove this extension piece from the cover (on 24 and 28 models). 2. Withdraw the burner from the cover and replace with the new one. 3. Examine the gasket, replacing if necessary. 4. Reassemble in reverse order. 14.7 Insulation (Fig. 75) 1. Remove the electrode leads, noting their positions. Also remove the electrodes as described in section 14.2. 2. Undo the screws securing the collector to the venturi and the nuts holding the cover to the heat exchanger. Draw the collector and cover assembly away. 3. Remove the cover insulation piece. 4. Fit the new insulation carefully over the burner and align it with the slots for the electrodes. 5. If the rear insulation requires replacement remove it and all debris from the heat exchanger. Also it may be necessary to separately remove the spring clip from the pin in the centre of the heat exchanger and the 'L' shaped clips embedded in the insulation. 6. DO NOT remove the shrinkwrapped coating from the replacement rear insulation. Keep the insulation vertical and press firmly into position. 7. Examine the cover seal and replace if necessary.
Page 60
14.8 Flue/Heat Exchanger Thermostat Sensor (Fig. 76) 1. Ease the retaining tab on the sensor away and disconnect the electrical plug. 2. Turn the sensor 90° anticlockwise to remove it is a bayonet connection. 3. Reassemble in reverse order. 14.9 Water Pressure Sensor (Fig. 78) 1. Drain the primary circuit. 2. Disconnect the two wires from the sensor. 3. Undo the nut on the flow pipe securing and sealing the sensor. 4. Remove the sensor, examine the sealing washer, replacing if necessary. 5. Reassemble in reverse order. The component is not polarised either wire will fit each terminal. Fig. 76 14.10 Central Heating Temperature Sensor (NTC) (Fig. 77) 1. Ease the retaining tab on the sensor away and disconnect the electrical plug. 2. Unscrew the sensor from it's pocket and reassemble in reverse order. The plug will only fit one way. 14.11 Safety Thermostat (Fig. 77) 1. Pull the plug off the thermostat. 2. Remove the screws securing the thermostat to the mounting plate on the flow pipe. 3. Reassemble in reverse order, ensuring that the plug is pushed fully on. 14.12 DHW Temperature Sensor (NTC) (Fig. 78) 1. Turn off the mains cold water supply tap and draw off the residual domestic hot water. 2. Ease the retaining tab on the sensor away and disconnect the electrical plug. 3. Unscrew the sensor from the plate heat exchanger manifold. Examine the sealing washer, replacing if necessary. 4. Reassemble in reverse order. The plug will only fit one way.
Page 61
Fig. 77 and Fig. 78 page 43 14.13 Pump Head Only (Fig. 79) 1. Drain the primary circuit and remove the socket head screws securing the pump head to the body and draw the head away. 2. Undo the screw on the pump wiring cover and remove the cover. Using a suitable flat bladed screw driver press the cable securing levers downwards to release each wire after noting their position. 3. A standard replacement Grundfos 1560 head can now be fitted. Connect the pump wiring to the new head. The pump speed must be set to 3 (Fig. 80). 4. Reassemble in reverse order. 14.14 Pump Complete (Fig. 81) 1. Drain the primary circuit. 2. Undo the two screws securing the body to the pipe and manifold and draw the pump forwards. 3. Undo the screw on the pump wiring cover and remove the cover. Using a suitable flat bladed screw driver press the cable securing levers downwards to release each wire after noting their position. 4. Unscrew the automatic air vent from the pump body. 5. Connect the wiring to the new pump. Examine the 'O' ring seals on the return pipe and manifold, replacing if necessary. 6. Fit the air vent to the pump body and reassemble in reverse order. 14.15 Automatic Air Vent (Fig. 81) 1. Drain the primary circuit and unscrew the automatic air vent from the pump body. 2. Examine the 'O' ring seal, replacing if necessary, and fit it to the new automatic air vent. 3. Reassemble in reverse order.
Page 63
1. Drain the primary circuit and undo the nut on the pressure gauge capillary. 2. Undo the screws securing the gauge retaining bracket. 3. Remove the bracket and gauge assembly. Depress the barbs on the side of the gauge and remove the retaining bracket. 4. Examine the sealing washer, replace if necessary. 5. Reassemble in reverse order. Fig. 82 Fig. 83 14.17 Hall Effect Sensor (Fig. 84) 1. Ease the sensor upwards off the hydraulic inlet manifold assembly. 2. Disconnect the electrical plug from the sensor. 3. Connect the plug to the new sensor. Carefully fit the new sensor to the hydraulic assembly, ensuring it is fully down. 14.18 Safety Pressure Relief Valve (Fig. 85) 1. Drain the primary circuit. 2. Disconnect the discharge pipe from the valve. Using a suitable hexagon key undo the grub screw sufficiently to release the valve. 3. Note the orientation of the valve, rotate it and withdraw it from the manifold. 4. Fit the new valve and 'O' ring seal and set to the previously noted orientation. Reassemble in reverse order.
Page 64
Fig. 84 and Fig. 85 page 45 14.19 Plate Heat Exchanger (Fig. 86) 1. Drain the primary circuit and remove the gas valve as described in section 14.23. 2. While supporting the heat exchanger undo the screws securing it to the brass manifolds. 3. Withdraw the heat exchanger upwards, taking care not to damage any wires or controls. Seals 4. There are four rubber seals between the manifolds and heat exchanger which may need replacement. 5. Ease the seals out of the manifold. Replace carefully, ensuring that when the seal is inserted into the manifold it is parallel and pushed fully in. 6. When fitting the new heat exchanger note that the left hand location stud is offset towards the centre more than the right hand one. 7. Reassemble in reverse order. 14.20 Diverter Valve Motor Unit & Assembly (Fig. 87) 1. To replace the motor unit, disconnect the multipin plug. 2. Pull off the retaining clip and remove the motor unit. 3. The motor unit can now be replaced, or the valve assembly removed. 4. Drain the primary circuit and draw off any hot water once the isolating taps are closed. 5. Undo the nuts on the tap rail under the boiler. Remove the screws securing the valve assembly to the boiler bottom panel and plate heat exchanger. 6. Remove the valve assembly. Examine any seals or washers, replacing if necessary. Transfer the DHW NTC to the new valve and reassemble in reverse order.
Page 65
Fig. 86 and Fig. 87 page 46 14.21 P.C.B. (Fig. 90) 1. Note the settings of the temperature control knobs, rotate them fully anticlockwise and carefully pull them off the drive pins. 2. Completely undo the screws securing the control box cover and release the cover retaining barbs from their slots. Disengage the rear of the cover from the control box hinge pin (Fig. 89). 3. Note the position of all plugs and wires on the P.C.B. and disconnect them. 4. Undo the securing screws and remove the P.C.B. Transfer the control knob drive pins to the new P.C.B. and turn them fully anticlockwise. 5. Reassemble in reverse order, ensuring that the temperature controllers are reset to their previous positions. 14.22 Selector Switch (Fig. 90) 1. Note the setting of the selector switch knob and carefully pull it off the facia. 2. Completely undo the screws securing the control box cover and release the cover retaining barbs from their slots. Disengage the rear of the cover from the control box hinge pin (Fig. 89). 3. Note the position of the electrical connections and the orientation of the switch. Remove the electrical connections. 4. Remove the screws securing the switch to the facia panel. 5. Fit the new switch, ensuring that it is correctly positioned and reassemble in reverse order.
Page 66
Fig. 89 and Fig. 90 page 47 14.23 Gas Valve (Fig. 91) IMPORTANT: After replacing the valve the CO must be checked and adjusted as detailed in Section 15.0 Setting the Gas Valve. Only change the valve if a suitable calibrated combustion analyser is available, operated by a competent person see section 13.1. 1. Turn the gas cock off and undo the nut on the gas feed elbow under the boiler. 2. Remove the screws securing the gas valve the boiler bottom panel. 3. Pull off the power lead, earth lead and sensing pipe. 4. Undo the nut on the gas pipe at the gas/air inlet and the gas valve. Remove the pipe, taking care not to lose the sealing washers. Remove the valve. 5. Reassemble in reverse order, ensuring that all seals are in place and the injector is fitted. 6. Reassemble in reverse order. NOTE: To assist the boiler to light prior to final setting, use a suitable hexagon key to wind out the Throttle Adjustment Screw until it is flush with the valve body, then turn the screw 4 full turns clockwise (Fig. 91a). If the boiler will not light, or the correct CO cannot be achieved contact the 'heateam' technical helpline. 14.24 Expansion Vessel (Fig. 92) 1. Drain the primary circuit and undo the nut on the vessel connection pipe. 2. Undo and remove the locknut securing the vessel spigot to the boiler air box.
Page 67
3. Remove the bracket and vessel from the boiler. 4. Locate the retaining bracket on the upper flange of the vessel and fit to the boiler. 5. Reassemble in reverse order.
Fig. 91, Fig. 91a and Fig. 92 page 48 15.0 Setting the Gas Valve 15.1 Setting the Gas Valve (CO check) 2 IMPORTANT: The CO must be only be checked and adjusted to set the valve if a suitable calibrated combustion analyser is available, operated by a competent person see Section 13.1 1. The combustion (CO ) may be checked after running the boiler for several minutes. To do this it is necessary to set the boiler to 'Calibration Mode'. 2. Ensure that all external controls are calling for heat. The actual current boiler temperature is shown on the display. 3. Turn both control knobs fully anticlockwise, then quickly turn the right hand knob 1/4 clockwise twice and back fully anticlockwise (Fig. 93). 4. The display will now alternate between 'SF' and the current boiler temperature and both green LEDs will flash (Figs. 94 & 95). 5. Turn the left hand knob fully clockwise. As the knob is turned the display will change, indicating the fan speed. 6. The display will show '00', indicating maximum rate, then revert to 'P ' alternating with the current boiler temperature (Figs. 96, 97 & 98). 7. Remove the plug from the flue sampling test point. Insert the analyser probe and allow sufficient time for the reading to settle (Fig. 99). The CO should be 8.7% ± 0.2 8. It is possible to alter the CO2 by adjustment of the gas valve. Remove the plastic cover from the Throttle Adjustment Screw. At maximum rate the Throttle Adjustment Screw should be turned, using a suitable hexagon key, until the correct reading is obtained (Fig. 100). Turning clockwise will reduce the CO . Anticlockwise will increase the CO 9. The CO must then be checked at minimum rate. Turn the left hand knob fully anticlockwise. As the knob is turned the display will change, indicating the fan speed. When the display reads ' 0' the boiler runs at minimum rate. The CO should be 8.4% ± 0.2 10. With the boiler on minimum, the Offset Adjustment Screw must be altered, using a suitable hexagon key, after removing the cap (Fig. 100). Turning anticlockwise will reduce the CO . Clockwise will increase the CO 11. The 'Calibration Function' is maintained for 20 minutes unless the maximum CH temperature is exceeded. The function can be disabled at any time by turning the right hand knob. 12. Check the Combustion Performance (CO/CO ratio). This must be less than 0.004. Fig. 93 Fig. 95 Fig. 94 ...
br brown g green bk black g/y green / yellow b blue red w white page 50 17.0 Short Parts List Short Parts List Key No. Description Manufacturers Part No. 5121447...
Page 73
1. Check that gas, water and electrical supplies are available at the boiler. 2. Electrical supply = 230V ~ 50 Hz. 3. CH water system pressurised to 0.5 bar minimum when the boiler is cold. 4. The preferred minimum gas pressure is 20 mbar. 5. Carry out electrical system checks, i.e. Earth Continuity, Resistance to Earth, Short Circuit and Polarity with a suitable meter. NOTE: These checks must be repeated after any servicing or fault finding. 6. Ensure all external controls are calling for heat and check all external and internal fuses. Before any servicing or replacement of parts, ensure the gas and electrical supplies are isolated. 18.2 Error Codes 1. If a fault occurs on the boiler an error code may be shown by the facia display. 2. The codes are either two or three digit, preceded by the letter 'E'. For example, code E133 will be displayed by 'E1' alternating with '33'. E50 is shown as 'E' then '50' E20, E28 & E50 indicate faulty components. E110 shows overheat of the primary water and E130 overheat of the flue system. E119 is displayed when the primary water pressure is less than 0.5 bar. E133 indicates that the gas supply has been interrupted, ignition has failed or the flame has not been detected. E125 is displayed in either of two situations: i) If within 15 seconds of the burner lighting the boiler temperature has not changed by 1°. ii) If within 10 minutes of the burner lighting the boiler temperature twice exceeds the selected temperature by 30°. In these instances poor primary circulation is indicated. 3. By turning the selector switch to the 'Reset' position for a minimum of 5 seconds when E110, E130 & E133 are displayed it is possible to relight the boiler. 4. If this does not have any effect, or the codes are displayed regularly further investigation is required. NOTE: When instructed to turn the selector to the reset position turn the selector switch fully anticlockwise against the spring pressure to the reset position and hold for 5 seconds to reset the boiler. Table Of Error Codes Central Heating NTC Fault Flue NTC Fault Hot Water NTC Fault E110 Safety Thermostat Operated E119 Water Pressure Switch Not Operated E125 Circulation Fault (Primary Circuit) E130 Flue NTC Operated E133 Interruption Of Gas Supply or Flame Failure E160 Fan or Fan Wiring Fault E193...
Page 74
page 53 Domestic Hot Water Follow operational sequence...
Page 78
page 57 GAS BOILER SYSTEM COMMISSIONING CHECKLIST...
Page 80
page 58 Service Record It is recommended that your heating system is serviced regularly and that the appropriate Service Interval Record is completed. Service Provider Before completing the appropriate Service Record below, please ensure you have carried out the service as described in the manufacturer's instructions. Always use the manufacturer's specified spare part when replacing controls.
Page 81
All descriptions and illustrations provided in this leaflet have been carefully prepared but we reserve the right to make changes and improvements in our products which may affect the accuracy of the information contained in this leaflet. All goods are sold subject to our standard Conditions of Sale which are available on request. BAXI A Trading Division of Baxi Heating UK Ltd (3879156) ...
Need help?
Do you have a question about the 47 075 35 and is the answer not in the manual?
Questions and answers