ACV International 427.10 Checking the gas air ratio control7.10.1 Checking flue gas at maximum power.1. Switch the appliance off with the button .[-] will appear in service display.2. Remove the front panel by untightening the 2 screws.3. Remove the cap X of the flue gas sampling point on the adapter.4. Position the measuring probe or the flue gas analyser into the sampling point.Important• Ensure yourself that the analyser start up procedure hasbeen finalized before placing the probe.• The probe needs to close the sampling point fully to ensurean accurate measurement• The end (tip) of the probe must be completely in the fluegasses (in the middle of the flue pipe).5. Switch the appliance on with the button .6. Activate the test program for maximum output by simultaneously pressing the buttonsand twice. A capital H appears in service display.Important• Make sure a capital H is shown in the display to ensure theappliance to run at maximum power.7. Wait until the reading of the flue gas analyser is stable (minimal 3 minutes)8. Note the measured value O2(H) or CO2(H)O2(H) = measured O2 value at maximum powerCO2(H) = Measured CO2 value at maximum power9. Check if the measured value is in accordance with the data noted in table 2a or 2b .Table 2a: Limits O2(H) at maximum power (open casing)Gas categoryLimits Natural gasG 20Propane 3PG31O2 [%] O2 [%]Maximum value 5.60 6.05Minimum value 3.85 4.50Tabel 2b: Limits CO2(H) at maximum power (open casing)LimitsGas categoryNatural gasG 20Propane 3PG31CO2 [%] CO2 [%]Maximum value 9.6 10.8Minimum value 8.6 9.8Important• A deviation at maximum power can not be adjusted with the gas valvesetting. When the value measured at maximum power is without theprescribed range the boiler has to be checked on gas tightness andusage of the correct components, in particular the gas ring, the insertand the fan.•10. Proceed performing the measurement on minimum output(see § 7.10.2).X03010020