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To maintain the boiler guarantee it is essential that the boiler is serviced annually by a Gas Safe registered engineer who has been trained on the boiler installed. The service details should be recorded on the Benchmark Service Interval Record and left with the householder.
Manufacturer's instructions must NOT be taken in anyway as over-riding statutory obligations. Notes: 1. Ensure that the Benchmark Checklist has been completed after the boiler has been installed and commissioned. 2. It is the law that all domestic boiler installations are registered by the installer through the Gas Safe Notification Scheme.
The user must not dispose of the appliance at the end of its service life as municipal waste, but send it to appropriate collection centres. PERSONAL PROTECTIVE EQUIPMENT SAFETY GLOVES SAFETY GOGGLES SAFETY FOOTWEAR Alpha E-Tec 20NXS, 30NXS and 35NXS - Safety Symbols and Information...
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Boiler operating weight (full of water) approx. E-Tec 20NXS 33.9 E-Tec 30NXS 36.2 36.2 E-Tec 35NXS Max. total flue length Horizontal Max. total flue length Vertical Flue system diameter 60/100 Alpha E-Tec 20NXS, 30NXS and 35NXS - Safety Symbols and Information...
2.23 (0.62) 2.54 (0.71) 2.95 (0.82) SAP/SEDBUK seasonality efficiency 2005 91.8 91.7 90.7 SAP/SEDBUK seasonality efficiency 2009 89.7 89.5 89.6 CO maximum Note: OtherTechnical data is the same as NG data. Alpha E-Tec 20NXS, 30NXS and 35NXS - Technical Data...
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When the pump is running, the symbol flashes with green light. When the pump power supply on, the symbol is steady with green light. If the pump detects an alarm, the symbol is steady with red light. Alpha E-Tec 20NXS, 30NXS and 35NXS - Technical Data...
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B = Head available with by-pass open C+D = Power consumed by the pump with by-pass open (dotted area) D = Power consumed by the pump with by-pass closed (dotted area) Fig. 3.2 Alpha E-Tec 20NXS, 30NXS and 35NXS - Technical Data...
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.....DHW minimum heat input nw min. Class ....NO Class .......CH minimum heat input n min. CONDENSING ..Condensing boiler ....DHW maximum heat input nw max.......CH maximum heat input n max. Alpha E-Tec 20NXS, 30NXS and 35NXS - Technical Data...
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Air vent drain valve Automatic air vent Gas isolation valve Venturi Primary heat exchanger Primary flow temperature sensor Boiler pump Ignition/sensing electrode Primary pressure switch Air supply pipe By-pass Fig. 3.4 Alpha E-Tec 20NXS, 30NXS and 35NXS - Technical Data...
2. Under no circumstances must the flue length (including allowances for extra bends) exceed 12 metres horizontally and only 14 metres vertically. 3. Failure to use Alpha flue components with the boiler will invalidate the boilers CE approval, guarantee and may be unsafe. Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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Fig. 4.1 VERTICAL FLUE OPTIONS Not less than 300 mm Not less than 300 mm Hmax = 14 m Hmax = 12.2 m (14 m - 1.8 m) Fig. 4.2 Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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Where a terminal is sited below 2 m from the ground or floor level, the terminal must be protected by a terminal guard. In these situations, consideration should also be given to prevent nuisance plume and fumes in areas such as access routes, passageways, patios, balconies etc. Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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The boiler may be installed in a cupboard or compartment, provided it is correctly designed for that purpose, i.e. complies with the Building Regulations and the requirements of BS 6798. Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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Hose unions Double check valve assembly Heating circuit Mains return water Stop Stop supply valve valve Test cock Filling loop temporarily connected Fig. 4.6 Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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Plastic pipe (minimum 32 mm) Ensure pipe is adequately supported Open end of pipe diverted into gully below grid but above water level Minimum gradient 2½° Fig. 4.7 - External gully Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
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Two rows of 3 x 12mm holes at 25mm centres, 50mm from the bottom Soakaway depth 400mm of the tube. Holes to face filled with limestone chippings away from house. Fig. 4.8 - External soakaway Alpha E-Tec 20NXS, 30NXS and 35NXS - General Boiler Information...
130 mm dia. flue hole using a 127 mm core drill. Drill the fixing holes (10 mm dia.) to accept the No.10 plugs Outline of supplied. Using the screws supplied, fit the mounting bracket. boiler Template Fig. 5.2 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Gas service cock (yellow) Heating flow valve Electrical connection Heating drain point A - Gas inlet - (22 mm) B - Heating return - (22 mm) C - Heating flow - (22 mm) Fig. 5.4 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Check the 60mm and 100mm double lip seal gaskets are fitted with the lips facing downwards. See Fig. 5.6. Flue turret Four fixing screws Gasket protruding rib facing downwards Fig. 5.5 Flue seal ribs must face downwards Flue turret gasket must be located as shown Fig. 5.6 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Alternatively plume management components can be used with supports where necessary. All joints between flue sections should be connected using the clamps provided. It is not required to add additional screws through the clamps and into the flue sections. Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Note: Ensure that all cuts are square and free from burrs. Once assembled with the components pushed home, the flue is fully sealed. Allow 20 mm 30 mm Do not cut past this point Fig. 5.12 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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25 - 30 mm per metre Inner seal joint Easy-Flue 45 mm clamp 90° bend Terminal Inner seal joint CD Flue extension Flue sealing collar Flue length (L) Front of boiler Fig. 5.13 - Side flue Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Plume Management 1000 mm extension 60 mm dia. (equivalent to 1 m flue length) - Part No. 6.2001310. 60 mm dia. wall bracket - Part No. 6.2001260. Plume kit (2 x 93° bends 1 x 1000 mm extension and wall bracket) - Part No. 6.2001300. Fig. 5.14 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Note: The equivalent horizontal flue assembly length + the equivalent plume management length (PM length) must not exceed the maximum flue length stated for each boiler, i.e. E-Tec boilers - the maximum equivalent flue length must not exceed 12 metres. Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Remove the links between terminal blocks 1 and 2. Replace the control panel cover in reverse order. Note: Ensure all wires and connections are secured safely before replacing covers. Fig. 5.18 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Note: The temperature of the radiators will vary depending on the outside temperature; the required room temperature will still be maintained by the room thermostat. 8 7 6 Max. System temperature (°C) Min. External temperature (°C) Fig. 5.19 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
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Configurable relay Parameter P3=5 remove the links between (diverter valve option) terminal blocks 1 and 2 CH ON contact closed CH OFF contact open 5 = Live CH On 6 = Neutral Fig. 5.21 Alpha E-Tec 20NXS, 30NXS and 35NXS - Installation...
COMMISSIONING When commissioning the boiler, ensure the Benchmark Checklist at the back of these instructions is completed. FILL THE SYSTEM The boiler is fitted with an automatic air vent positioned on the pump (see Fig. 7.8), ducted to the bottom of the boiler casing and is NOT to be blocked.
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The lighting mode can be varied via parameter 't8' in the PCB programming menu. For any controls fitted please refer to the instructions supplied with the controls for connection and operation details and Section 5.11. Alpha E-Tec 20NXS, 30NXS and 35NXS - Commissioning...
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24 hours. CHECKING THE COMBUSTION - CHIMNEY SWEEP MODE As part of the Benchmark Checklist procedure the combustion levels of the boiler when the installation is completed must be measured and recorded. The air gas ratio of the boiler has been factory-set and should not require adjusting during commissioning. If adjustment is recommended or required the engineer must be competent to carry out this work.
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Show the User the position of the condensate discharge pipes. 10. Leave the instructions with the User. 11. Ensure the Benchmark Checklist at the back of these instructions has been completed after the boiler has been installed and commissioned. Note: It is a requirement that the installation is registered by the installer through the Gas Safe Gas Work Notification Scheme.
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Using an indelible marker pen, delete the data relative to the old type of gas. These adjustments must be made according to the type of gas used, given in the table (Section 3). Alpha E-Tec 20NXS, 30NXS and 35NXS - Commissioning...
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F (+) A (-) Outlet pressure test point Gas outlet flow Inlet pressure adjustment screw test point (Max. CO ) Off/Set adjustment screw (Min. CO ) Wiring plug Fig. 6.2 Fig. 6.3 Alpha E-Tec 20NXS, 30NXS and 35NXS - Commissioning...
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1 - OpenTherm type remote control - Boiler terminal block link 1 protocol setting to 2 must be present 2 - Not used on this model Common flue Not used on this model Alpha E-Tec 20NXS, 30NXS and 35NXS - Commissioning...
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Value below the cylinder set point to activate cylinder heating (the 0 - 15 activation cylinder heating OFF is fixed at the cylinder DHW set point value) temperature (Alpha Diverter kit required) Not used on this model Alpha E-Tec 20NXS, 30NXS and 35NXS - Commissioning...
Section 7.1 and Section 7.3 paragraphs 1, 2 and 3 need to be carried out to allow a visual check of the components within the room sealed chamber. Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
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Pull the combustion panel 'E' slightly towards you. Release the combustion panel 'E' from the pins 'F' pulling it towards you while pushing it upwards at the same time. Fig. 7.1 Fig. 7.2 Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
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10. Lower the panel out and away from the top cover. Note: The side panels require no sealing strip as the front case insulation forms the room seal. View A Fig. 7.4 Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
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Check the condition of the burner injector in the gas valve outlet, carefully clean with a soft brush if necessary - Do not use a brush with metallic bristles as this might damage the injector. Unscrew and replace the injector should it appear damaged. Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
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(Fig. 7.1). 11. Check the operation of the boiler. (Refer to Sections 6.5 and 6.6). 12. Return all controls to their original settings. Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
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Gas injector 3 bar safety valve Gas valve By-pass Boiler drain point Safety valve operation indicator Test points (air A, flue F) Pressure signal vent fitting Flue temperature sensor Fig. 7.8 Alpha E-Tec 20NXS, 30NXS and 35NXS - Routine Servicing...
Unplug the wire from the flue sensor. Using a 13 mm spanner, turn the sensor 90° anti-clockwise and withdraw it from the heat exchanger. Fit the new sensor and re-assemble in reverse order. Alpha E-Tec 20NXS, 30NXS and 35NXS - Component Replacement...
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Turn the automatic air vent anticlockwise and lift it out. Insert the new air vent and turn it clockwise to lock it in position. Reassemble the silicone tube and clip. Refill and pressurise the system. (Refer to Commissioning, Section 6.1). Alpha E-Tec 20NXS, 30NXS and 35NXS - Component Replacement...
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Using a 4 mm Allen key remove the four socket head screws securing the pump head to the body. Reassemble the new pump head in reverse order, re-connecting the two wiring connectors. Refill and pressurise the system. (Refer to Commissioning, Section 6.1). Alpha E-Tec 20NXS, 30NXS and 35NXS - Component Replacement...
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11. Test the boiler, check the ignition and test the combustion as described in Section 7. 8.21 ALPHA CONTROLS (if fitted) Refer to Section 5.11 on the connection options for boiler controls. Alpha E-Tec 20NXS, 30NXS and 35NXS - Component Replacement...
Control panel button stuck in the on position Check for jammed control panel buttons fault Check for jammed PCB buttons * When external zone valves are fitted an external by-pass must also be installed. Alpha E-Tec 20NXS, 30NXS and 35NXS - Error Codes and Fault Finding...
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Possible failure of one or both sensors Check sensor resistance fault Return/flow sensor Possible failure of one or both sensors Check sensor wiring and connections fault Check sensor resistance Alpha E-Tec 20NXS, 30NXS and 35NXS - Error Codes and Fault Finding...
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Pump with UPM4 Pump fault Possible causes for this anomaly: electronics ONLY 1. Low power supply voltage 2. Seized rotor Symbol with 3. Electrical fault steady red light Alpha E-Tec 20NXS, 30NXS and 35NXS - Error Codes and Fault Finding...
(*) High temperature regime means 60°C return temperature at heater inlet and 80°C feed temperature at heater outlet. (**) Low temperature means for condensing boilers 30°C, for low-temperature boilers 37°C and for other heaters 50°C return temperature. Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
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Yearly electricity consumption for the domestic hot water function (AEC) Yearly fuel consumption for the domestic hot water function (AFC) Seasonal room heating yield (ηs) 94 % 94 % 94 % Domestic hot water production yield (ηwh) Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
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Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
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Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
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* To be established by means of table 5 of Regulation 811/2013 in case of “assembly” including a heat pump to integrate the boiler. In this case the boiler must be considered as the main appliance of the assembly. Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
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Parameter E-Tec 20NXS E-Tec 30NXS E-Tec 35NXS ‘I’ ‘II’ ‘III’ * To be determined according to Regulation 811/2014 and transient calculation methods as per Notice of the European Community no. 207/2013. Alpha E-Tec 20NXS, 30NXS and 35NXS - Energy Classification...
Where possible, has a flue integrity check been undertaken in accordance with manufacturers’ instructions, and readings are correct? The operation of the boiler and system controls have been demonstrated to and understood by the customer The manufacturers’ literature, including Benchmark Checklist and Service Record, has been explained and left with the customer Commissioning Engineer’s signature Customer’s signature...
SERVICE & INTERIM BOILER WORK RECORD It is recommended that your boiler and heating system are regularly serviced and maintained, in line with manufacturers’ instructions, and that the appropriate service / interim work record is completed. Service provider When completing a service record (as below), please ensure you have carried out the service as described in the manufacturers’ instructions. Always use the manufacturers’...
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SERVICE & INTERIM BOILER WORK RECORD It is recommended that your boiler and heating system are regularly serviced and maintained, in line with manufacturers’ instructions, and that the appropriate service / interim work record is completed. Service provider When completing a service record (as below), please ensure you have carried out the service as described in the manufacturers’ instructions. Always use the manufacturers’...
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SERVICE & INTERIM BOILER WORK RECORD It is recommended that your boiler and heating system are regularly serviced and maintained, in line with manufacturers’ instructions, and that the appropriate service / interim work record is completed. Service provider When completing a service record (as below), please ensure you have carried out the service as described in the manufacturers’ instructions. Always use the manufacturers specified spare parts.
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