Vaillant HOME System (12 -A, 15 -A, 18 -A, 25 -A)
System boiler, natural gas
Combustion figures
| Figure | Natural gas (G20) |
|---|---|
CO₂ at high rate More infoHide infoCheck programme P.01 set to 100, read after 5 minutes when stable, at the flue gas analysis point. The checking table (MI 7.9.4 and 11.3) gives ±1 % with the front casing removed or installed; if outside this, set it (MI 11.4) to ±0.2 % with the front casing removed, turning the CO₂ screw 1/8 turn at a time and waiting about 1 minute after each turn. Set for Wobbe index 14.09 kW·h/m³. |
|
CO₂ at low rate | Not given in MI |
Maximum CO More infoHide infoThe setting table (MI 11.4) gives ≤ 250 ppm at full load. The combustion chart (Appendix I) gives less than 350 ppm at max and min rate; one box of the chart (after checking seals) says less than 335 ppm instead. |
|
CO/CO₂ ratio More infoHide infoThe setting table (MI 11.4) gives ≤ 0.0027. The combustion chart (Appendix I) gives less than 0.004 at max and min rate. |
|
O₂ at high rate More infoHide infoFrom the setting table (MI 11.4), O₂ at full load. | 4.5 ±1.8 vol. % |
O₂ at low rate | Not given in MI |
Working inlet pressure More infoHide infoMeasured at the measuring nipple on the gas isolator cock, boiler at full load (check programme P.01) with all other gas appliances working. MI prints 1.7 ... 2 kPa (17.0 ... 20 mbar). Technical data gives G20 gas supply pressure 20 mbar. |
|
Gas rate at maximum More infoHide infoMI gives this as gas flow at P max. in hot water mode (G20). No heating mode gas rate is given. |
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Flue integrity More infoHide infoAt the air analysis point, boiler at maximum rate (combustion chart, Appendix I). | O₂ ≥ 20.6% CO₂ < 0.2% |
From 0020224357_00 (14.10.2015)
Enter service mode for high and low rate
High rate
Steps not added yet. Follow the MI.
Low rate
Steps not added yet. Follow the MI.
Ending the test: follow the MI.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| HOME SYSTEM 12 -A (H-GB) | 41-044-94 | NG |
| HOME SYSTEM 15 -A (H-GB) | 41-044-95 | NG |
| HOME SYSTEM 18 -A (H-GB) | 41-044-96 | NG |
| HOME SYSTEM 25 -A (H-GB) | 41-044-97 | NG |
Source: Vaillant HOME SYSTEM installation and maintenance instructions, 0020224357_00 (14.10.2015).
Sections: 2.3 Applicability of the instructions; 7.9.1 Checking the gas connection pressure; 7.9.2 Checking the leak-tightness of the flue gas system and for flue gas recirculation; 7.9.4 Checking the CO2 content; 11.3 Checking the CO2 content; 11.4 Setting the CO2 content; A Check programmes; I Combustion chart; K Technical data.
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Check these figures against the MI for the appliance in front of you, matched by GC number and manual date. Combustion work needs a calibrated analyser and a Gas Safe registered engineer.