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British Gas Checked against MI

British Gas British Gas 330 heat only (330)

Heat only, natural gas

Combustion figures

FigureNatural gas (G20)
CO₂ at high rate
More infoHide infoBurner CO₂ from Tables 2 and 4. The combustion check (MI 11.8) and gas valve setting (MI 13.5) give 9.1% ± 0.3 at maximum with the front and inner casing panels off. Range rated by fan setting: maximum is the rated output on the data label, factory set at 18 kW.
Case off
9.1% +0.3 −0.3
Case on
9.3% +0.3 −0.3
CO₂ at low rate
More infoHide infoFrom MI 13.5, at minimum (fan 1200 rpm, display flashing 12), with the front and inner casing panels off.
9.1% +0.3 −0.3
Maximum CO
Not given in MI
CO/CO₂ ratio
Not given in MI
O₂
Not given in MI
Working inlet pressure
More infoHide infoSteady inlet working pressure at the boiler from the governed meter (MI 1.3). At the gas valve inlet test point with the boiler at full rate (MI 10.6).
Appliance inlet
20 mbar
Gas valve test point
20 mbar
Gas rate at maximum
More infoHide infoApproximate gas rates for each range rated output (Tables 2 and 4). Factory set at 18 kW. Minimum: 0.67 m³/h (Table 2). Check at least 10 minutes after the burner has lit.
31 kW
3.31 m³/h
24 kW
2.54 m³/h
18 kW
1.90 m³/h
15 kW
1.59 m³/h
12 kW
1.27 m³/h

From 0020008877-04 08.06

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
33041-047-75NG

Source: British Gas 330 High Efficiency Condensing Boiler Instructions for Use, Installation and Servicing, 0020008877-04 08.06.

Sections: 1.3 Gas Supply; 1.4 Technical Data (Table 2); 10.5 Range Rating (Table 4); 10.6 Testing - Gas; 11.8 Combustion Check; 13.5 Gas Valve.

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.