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Baxi Checked against MI

Baxi EcoBlue Advance Combi (24, 28, 33, 40)

Combi, natural gas

Combustion figures

FigureNatural gas (G20)
CO₂ at high rate
More infoHide infoCase front panel fitted, system cold, after running the boiler for several minutes in chimney sweep mode. The manual says the valve is checked and set at maximum DHW input (setting 2).
8.7% ± 0.2
CO₂ at low rate
More infoHide infoMinimum input (setting 1) in chimney sweep mode.
8.4% ± 0.2
Maximum CO
More infoHide infoChecked at maximum and at minimum rate, at the flue gas test point, after the reading has stabilised.
< 350 ppm
CO/CO₂ ratio
More infoHide infoChecked at maximum and at minimum rate.
< 0.004
O₂
Not given in MI
Working inlet pressure
More infoHide infoAppliance inlet is the gas cock test point (Fig. 41a). At the gas meter: 19–23 mbar. Section 7.5.1 also says the working pressure at the inlet test point on the gas cock, at maximum rate, must be at least 17 mbar, and the technical data gives a nominal inlet pressure of 20 mbar. Permissible drop across system pipework ≤ 1 mbar.
Appliance inlet
18–22 mbar
Gas valve test point
17–21 mbar
Gas rate at maximum
More infoHide infoNatural gas (G20), after 10 minutes, with any other appliances and pilot lights turned off.
24
2.61 m³/h
28
3.05 m³/h
33
3.59 m³/h
40
4.35 m³/h
Flue integrity
More infoHide infoAt the air inlet test point, boiler at maximum rate.
O₂ ≥ 20.6%
CO₂ < 0.2%

From 7219715 - 02 (09/16)

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

ModelGC numberGas
EcoBlue Advance 24 Combi ErPD47-077-14NG
EcoBlue Advance 28 Combi ErPD47-077-15NG
EcoBlue Advance 33 Combi ErPD47-077-16NG
EcoBlue Advance 40 Combi ErPD47-077-17NG

Source: Baxi EcoBlue Advance Combi 24 - 28 - 33 - 40 Installation and Service Manual, 7219715 - 02 (09/16).

Sections: 3.1 Technical Data; 7.4.1 Checking Combustion - Chimney Sweep Mode; 7.5.1 Check the Operational (Working Gas Inlet Pressure & Gas Rate); 10.1 General; 10.3.25 Setting the Gas Valve (CO₂ Check).

Spotted something wrong? Tell us.

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.