Baxi 800 Heat (816, 825, 830)
Heat only (regular), natural gas
Combustion figures
| Figure | Natural gas (G20) |
|---|---|
CO₂ at high rate More infoHide infoFrom Setting the gas valve (MI 10.3.11), maximum rate in Chimney Sweep mode. The MI says there must always be a difference of 0.4% between the maximum and minimum CO₂ readings. | 9.3% ±0.1% |
CO₂ at low rate More infoHide infoFrom Setting the gas valve (MI 10.3.11), minimum rate in Chimney Sweep mode. | 8.9% ±0.1% |
Maximum CO More infoHide infoAt both maximum and minimum rate, at the flue gas test point (combustion check flow chart, MI 7.4.2). | < 350 ppm |
CO/CO₂ ratio More infoHide infoAt both maximum and minimum rate (MI 7.4.2). Technical data (MI 3.1) words it as up to a maximum of 0.004; MI 7.4.2, 10.1 and 10.3.11 say less than 0.004. | < 0.004 |
O₂ | Not given in MI |
Working inlet pressure More infoHide infoAt the gas meter: 19–23 mbar. Checked with the boiler at maximum rate; the text says at least 17 mbar at the valve and 18 mbar at the gas cock (MI 7.5.1, Fig. 41). Technical data gives a nominal dynamic inlet pressure of 20 mbar. |
|
Gas rate at maximum More infoHide infoNatural gas G20, after 10 minutes (MI 3.1). |
|
Flue integrity More infoHide infoAt the air inlet test point, boiler at maximum rate (MI 7.4.2, 10.1). | O₂ ≥ 20.6% CO₂ < 0.2% |
From 7749898-01 (3/20)
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 |
|---|---|---|
| Baxi 816 Heat | 41-470-77 | NG |
| Baxi 825 Heat | 41-470-78 | NG |
| Baxi 830 Heat | 41-470-79 | NG |
Source: Baxi 800 Heat Installation and Service Manual, Gas Fired Wall Mounted Condensing Boiler, 7749898-01 (3/20).
Sections: 3.1 Technical Data; 7.4.1 ’Chimney Sweep’ Mode (CSM); 7.4.2 ’Chimney Sweep’ Mode - Combustion Check; 7.5.1 Check the Operational (Working) Gas Inlet Pressure; 10.1 General; 10.3.11 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.