Installation and maintenance Avoiding danger arising from insufficient water pressure............... 26 instructions Flushing the heating installation for the first time ("cold") ............26 Contents Filling and purging the heating installation ..26 Filling the domestic hot water circuit....27 Safety ..............3 Checking the gas setting ........
Safety Qualification The person carrying out the work described Intended use here must have completed professional train- The product is intended as a heat generator ing. The competent person must demon- for closed heating installations and for do- strably have all of the knowledge, skills and mestic hot water generation.
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▶ Do not use any electrical switches, mains To prevent electric shocks, proceed as fol- plugs, doorbells, telephones or other com- lows before working on the product: munication systems in the building. ▶ Disconnect the product from the power ▶ Close the emergency control valve or the supply by switching off all power supplies main isolator.
List of relevant standards for Great Britain and Ireland ▶ Observe the national regulations, stand- ards, directives, ordinances and laws. You can find a list of relevant standards at: https://www.vaillant.co.uk/standards 0020230531_06 ecoFIT pure Installation and maintenance instructions...
To register your Vaillant appliance visit: https://self-service.vaillant.co.uk/warranty-registration Vaillant is a licensed member of the Benchmark Scheme. Benchmark places responsibilities on both manufacturers and installers. The purpose is to ensure that customers are provided with the correct equipment for their needs, that it is installed, commissioned and serviced in accordance with the manufacturer’s instructions by a competent person approved at the time by the Health and...
Technical data Technical data – General VUW 256/6-3 (H- VUW 306/6-3 (H- VUW 356/6-3 (H- Gas category Diameter of the gas pipe 1/2 inch 1/2 inch 1/2 inch Diameter of the heating connec- 3/4 inch 3/4 inch 3/4 inch tions Expansion relief valve connection 15 mm 15 mm...
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VUW 256/6-3 (H- VUW 306/6-3 (H- VUW 356/6-3 (H- Effective output range (P) 5.3 to 19.1 kW 6.3 to 26.5 kW 7.5 to 26.7 kW at 50/30 °C Effective output range (P) 5.0 to 18.3 kW 6.1 to 25.4 kW 7.2 to 25.6 kW at 80/60 °C Domestic hot water heat...
Notes on the documentation Information on the Meaning identification plate ▶ Always observe all operating instructions enclosed with Maximum water pressure in hot water the installation components. handling mode ▶ Store these instructions and all other applicable docu- V/Hz Electrical connection ments for further use.
Reset any external controls, to resume normal operation of the central heating. If the boiler does not resume normal operation press the reset button. If the boiler does not resume normal operation after this call your Installation/Servicing company or Vaillant service. 5.4.2 Overheating Safety The boiler software is designed to recognise the potential for an overheat lockout and will shutdown before this happens.
Set-up Dimensions Checking the scope of delivery ▶ Check that the scope of delivery is complete and intact. Number Designation Heat generator Unit mounting bracket Flexible condensate discharge pipe 3/4" seals 1/2" seals Service valve Gas stopcock Filling loop Connection pipe (heating flow and return) Cold water connection pipe Domestic hot water connection pipe Gas pipe...
Installation site Air/flue pipe 6.6.1 Regulation This boiler is not suitable for outdoor installation. This boiler may be installed in any room. However if the boiler is being Different flue outlet configurations can be carried out. installed in a room containing a bath or shower it must only be installed in zones 2 or 3.
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6.6.2 Position of the air/flue terminal 6.6.2.1 Positioning the terminal of a fan-supported flue system Dimen- Installation site sions Adjacent to a boundary. 300 mm The dimension below eaves, balconies and car ports can be reduced to this value, as long as the flue terminal is 25 mm extended to clear any overhang.
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Dimen- Installation site sions Below eaves. 200 mm Below gutters, pipe and drains. 75 mm The dimension below eaves, balconies and car ports can be reduced to this value, as long as the flue terminal is 25 mm extended to clear any overhang. External flue joints must be sealed with suitable silicon sealant. Above adjacent ground or balcony.
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6.6.3.3 Vertical Concentric Flue ⌀ 60/100 mm or 6.6.3 Flue Configuration Description ⌀ 80/125 mm (C33 type installation) 6.6.3.1 Horizontal Concentric Flue ⌀ 60/100 mm or ⌀ 80/125 mm (C13 type installation) Gasket (fitted) Consult the separate installation manual for air/flue gas sys- Note tems supplied with your appliance for all possibilities and as- If the terminal is at less than 1.80 m from the...
Removing/installing the front casing Boiler Final storey Inspection hatch Ground floor 6.9.1 Front casing, removing Note The flue connecting from the appliance to the flue system must be supplied from the manufacturer of the boiler. C43 flue systems must not be a 'pressurised sys- tem' but act under natural draught principles.
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6.10.2 Installing the side section ▶ Refit the components in the reverse order. 0020230531_06 ecoFIT pure Installation and maintenance instructions...
Installation Gas and water connections Preparing for installation ▶ Make sure that the existing gas meter is capable of passing the rate of gas supply required. ▶ Consider the maximum heat output given in DHW mode. ▶ Install a system separator (to be provided on-site) directly on the cold water connection for the combi boiler.
Connecting the condensate discharge pipe 7.6.1.1 Direct Connection to internal soil and vent stack Ø22mm ▶ Follow the instructions listed here and observe the legal Preferred option and local regulations on condensate discharge. ▶ Use PVC or any other material that is suitable for drain- 7.6.1.2 Direct connection to external soil and vent ing the non-neutralised condensate.
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7.6.1.7 External termination into rain water down Preferred option for external termination pipe 7.6.1.5 External termination into soakaway Ø32mm ≤ 3 m ≤ 3 m < 500 mm Ø22mm 100 mm Ø 32mm Ø12 NB only combined foul/rainwater drain 7.6.1.8 Additional methods of introducing air breaks Ground (either/or) Bottom of sealed tube Seal...
Flue installation 7.8.3 Cable route 7.7.1 Installing and connecting the air/flue pipe You can find out which air/flue pipes may be used by consulting the enclosed set-up instructions for the air/flue system. Observe the information on positioning the air/flue ter- minal.
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7.8.5 Establishing the power supply 230V~ Carry out the wiring. (→ Page 21) 10. Close the electronics box. Observe all valid regulations. 11. Make sure that access to the power supply is always Ensure that the nominal mains voltage is 230 V. available and is not covered or blocked.
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Condition: When connecting a control (230 V). 230V~ ▶ Connect the control to the main plug. ▶ Remove the bridge from the 24V=RT plug. Close the electronics box. 0020230531_06 ecoFIT pure Installation and maintenance instructions...
Operation Live Monitor (status codes) Menu → Live monitor Operating concept Status codes in the display provide information on the pro- The operating concept and the display and setting facilities duct's current operating status. of the operator level are described in the operating instruc- Status codes –...
Start-up Total Water hardness at specific system volume heating > 20 l/kW output ≤ 20 l/kW Carrying out the initial start-up > 50 l/kW ≤ 50 l/kW Initial start-up must be carried out by a customer service mol/ mol/ mol/ technician or an authorised competent person using the CaCO₃...
Additives for frost protection intended to remain Avoiding danger arising from insufficient permanently in the installation water pressure – Adey MC ZERO The filling pressure must be between 0.10 and 0.15 MPa – Fernox Antifreeze Alphi 11 (1.0 and 1.5 bar). –...
If you discover unusual levels of CO or CO in the sup- ply air, search for the leak in the flue system or for signs of flue gas recirculation. Eliminate the damage properly. Check again whether the supply air contains any unusal levels of CO or CO If you cannot eliminate the damage, do not start up the product.
9.9.4 Checking the CO₂ content Undo the sealing screw on the test nipple (2). Connect a manometer to the test nipple (2). Start up the product with check programme (P.01). Open the gas stopcock (1). Wait until the value that is read is stable. Start up the product with check programme P.01 (in- –...
Install the front casing. (→ Page 16) Set maximum burner anti-cycling time [min] Flow (tar- 9.11 Checking leak-tightness get) [°C] ▶ Check the gas pipe, the heating circuit and the hot water 12.0 14.0 circuit for leak-tightness. ▶ 10.0 11.5 Check that the air/flue pipe has been installed correctly.
10.3 Setting the bypass valve Caution. Risk of material damage caused by incor- rect setting of the high-efficiency pump If the pressure at the bypass valve is in- creased (by turning it clockwise) and the pump output is set to less than 100%, the product may not operate correctly.
Condition: Water hardness: > 3.57 mol/m³ – Domestic hot water temperature: ≤ 50 ℃ Descale the water as required. 11 Handing over to the end user ▶ At the time of commissioning complete all relevant sec- tions of the Benchmark commissioning checklist, located at the rear of this document.
12 Inspection and maintenance 12.5 Setting the CO₂ content Condition: The CO₂ content must be adjusted 12.1 Complete Service Interval Record section ▶ After servicing, complete the relevant Service Interval Record section of the Benchmark Checklist located on the inside back pages of this document. 12.2 Using original seals If you replace components, use only the enclosed original...
10. Remove the burner seals (7) and the burner (8). 11. Check the burner and the heat exchanger for damage and dirt. 12. If necessary, clean or replace the components accord- ing to the following sections. 13. Install the two new burner seals. 12.7 Cleaning the heat exchanger Remove the screw (1).
– 12.12 Cleaning the heating filter Clearance for the ignition electrodes: 3.5 to 4.5 mm Make sure that the seal (5) is free from damage. ▽ If necessary, replace the seal. 12.10 Cleaning the condensate trap Drain the product. (→ Page 35) Remove the temperature sensor (1).
12.14 Draining the product 13.2 Calling up and clearing the fault memory Close the service valves of the product. The last 10 fault messages are stored in the fault memory. ▶ Start check programme P.05. Call up the installer level. (→ Page 24) ▶...
13.5 Replacing defective components 13.5.1 Replacing the burner Remove the gas-air mixture unit. (→ Page 32) Remove the two burner seals. Remove the burner . Insert the new burner. Insert two new burner seals in the burner hood. Install the gas-air mixture unit. (→ Page 34) 13.5.2 Replacing the gas-air mixture unit Remove the gas-air mixture unit.
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13.5.4 Replacing the pump head 13.5.6 Replacing the PCB Disconnect the pump cables from the electronics box. Undo the four screws (1). Remove the pump head (2). Replace the O-ring. Use four screws to secure the new pump head. Connect the pump cables to the electronics box. Open the electronics box.
Dispose of the packaging correctly. ▶ 13.5.9 Replacing the volume flow sensor Observe all relevant regulations. ▶ For detailed information refer to www.vaillant.co.uk. Pull out the plug. Remove the volume flow sensor (1). Install the new volume flow sensor. Plug in the plug.
Appendix Inspection and maintenance work The table below lists the manufacturer requirements with respect to minimum inspection and maintenance intervals. If na- tional regulations and directives require shorter inspection and maintenance intervals, you should observe these instead of the intervals listed. Each time inspection and maintenance work is carried out, carry out the required preparatory and com- pletion work.
Maintenance work Interval Checking the pre-charge pressure of the expansion vessel at regular intervals Check the water flow rate (domestic hot water). Insufficient water flow Annually rate → Check the incoming water supply. Incoming water supply sufficient, water flow rate too low → Clean or replace the strainer in the cold water inlet Check the impeller sensor for dirt/damage and, if required, replace it Annually...
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Dia- Values Default set- gnostics Parameter Unit Increment, select, explanation Own setting ting Min. Max. code – d.14 Operating mode of the 0 = variable rotational speed Adjustable modulating pump (auto) 1; 2; 3; 4; 5 = Fixed rotational speeds → Section "Setting the pump output"...
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Dia- Values Default set- gnostics Parameter Unit Increment, select, explanation Own setting ting Min. Max. code – d.28 Function of relay 2 1 = Circulation pump Adjustable (multi-functional module) 2 = External pump 3 = Cylinder charging pump 4 = Extractor hood 5 = External solenoid valve 6 = Fault display 7 = Solar pump (omitted)
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Dia- Values Default set- gnostics Parameter Unit Increment, select, explanation Own setting ting Min. Max. code – – – d.69 Number of unsuccessful Current value ignitions at 2nd attempt adjustable – d.70 Operation of the diverter 0 = Normal operating mode Adjustable valve (DHW and heating mode)
Status codes – Overview Note Since the code table is used for various products, some codes may not be visible for the product in question. Status code Meaning Displays in heating mode Heating mode: No requirement S.01 Heating mode: Fan prerun S.02 Heating mode: Pump prerun S.03...
Status code Meaning S.98 Automatic test programme: Return temperature sensor, heating demands blocked. S.99 Internal automatic test programmes S.108 Purging the combustion chamber, fan in operation S.109 Product's standby mode activated Overview of fault codes Note Since the code table is used for various products, some codes may not be visible for the product in question. Fault code Meaning Possible cause...
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Fault code Meaning Possible cause F.67 Value sent back by ASIC is incorrect Implausible flame signal, electronics defective (flame signal) F.68 Fault: Unstable flame (analogue input) Air in gas, gas flow pressure too low, incorrect air ratio, incorrect gas in- jector, ionisation flow interruption (cable, electrode) F.70 Invalid product code (DSN)
Commissioning Checklist Benchmark Commissioning & Warranty Validation Service Record It is a requirement that the boiler is installed and commissioned to the manufacturers’ instructions and the data fields on the commissioning checklist completed in full. To instigate the boiler warranty the boiler needs to be registered with the manufacturer within one month of the installation.
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GAS BOILER SYSTEM COMMISSIONING CHECKLIST & WARRANTY VALIDATION RECORD Address: Boiler make and model: Boiler serial number: Commissioned by (PRINT NAME): Gas Safe registration number: Company name: Telephone number: Company email: Company address: Commissioning date: Heating and hot water system complies with the appropriate Building Regulations? Time, temperature control and boiler interlock provided for central heating and hot water Boiler Plus requirements (tick the appropriate box(s)) Weather compensation...
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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 SERVICE/INTERIM WORK ON BOILER Date: SERVICE/INTERIM WORK ON BOILER...
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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 SERVICE/INTERIM WORK ON BOILER Date: SERVICE/INTERIM WORK ON BOILER...
Commissioning Flow Chart PRIOR TO CO AND COMBUSTION RATIO CHECK NOTE The boiler manufacturer’s installation instructions should have been followed, gas type verified and gas THE AIR GAS RATIO VALVE IS FACTORY supply pressure/rate checked as required prior to commissioning. SET AND MUST NOT BE ADJUSTED As part of the installation process, especially where a flue has been fitted by persons other than the DURING COMMISSIONING UNLESS THIS...
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