Worcester Bosch Greenstar 2000 combi (GR2300iW 25 C, 30 C)
Combi, natural gas
Combustion figures
| Figure | Natural gas (G20) |
|---|---|
CO₂ at high rate More infoHide infoBoiler at maximum in chimney sweep mode, combustion cover on, measured 10 minutes after firing, at the flue gas sample point. The technical data (MI 13.1) gives 9.4% (9.3% in its Low NOx column) for both sizes. | Between 9.0 and 10.8% |
CO₂ at low rate More infoHide infoBoiler at minimum in chimney sweep mode, combustion cover on, allowed to stabilise. The technical data (MI 13.1) gives 8.6% for both sizes, after 10 minutes. | A minimum of 0.6 lower than the maximum reading taken but above 8.2% |
Maximum CO More infoHide infoThe manual doesn’t agree with itself. The commissioning flow chart (MI 6.9, Fig. 65) uses CO < 350 ppm at maximum and minimum. The service table (MI 9.6, Table 31) gives <250 ppm at maximum and minimum. |
|
CO/CO₂ ratio More infoHide infoFrom the commissioning flow chart (MI 6.9, Fig. 65), at maximum and minimum. MI 6.7 refers to the technical data for CO/CO₂ ratios, but the technical data table doesn’t list one. | <0.004 |
O₂ at high rate More infoHide infoFrom the service table (MI 9.6, Table 31), alongside the CO₂ figures. | 4.0% |
O₂ at low rate More infoHide infoFrom the service table (MI 9.6, Table 31), alongside the CO₂ figures. | 5.5% |
Working inlet pressure More infoHide infoBoiler at maximum in chimney sweep mode, with heat taken away through the radiators. At the meter: 19–23 mbar. Allowed drop: 1 mbar across the pipework, 1.5 mbar across the appliance. |
|
Gas rate at maximum More infoHide info10 minutes from lighting, from the technical data (MI 13.1). Measure at the meter after at least 10 minutes at maximum in service mode, with all other gas appliances off (MI 6.7). |
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Flue integrity More infoHide infoAt the air inlet sample point on the flue turret/adaptor, combustion casing on, boiler at maximum in chimney sweep mode (MI 6.10). The text in 6.10 lists both readings, but the flow chart (Fig. 65) says O₂ ≥ 20.6% or CO₂ < 0.2%. | O₂ ≥ 20.6% CO₂ < 0.2% |
From 6 721 820 552 (2020/07)
Enter service mode for high and low rate
High rate
- Hold ok for at least 5 seconds. The chimney sweep symbol shows and it goes to maximum by itself.
- Display shows 100% alternating with the flow temperature.
Low rate
- Press ▼ for minimum. Display shows the minimum % alternating with the flow temperature.
Ending the test
- Press ok to come out. It also ends by itself after 30 minutes.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| GR2300iW 25 C NG | 47-800-26 | NG |
| GR2300iW 30 C NG | 47-800-28 | NG |
Source: Greenstar 2000 GR2300iW C gas-fired condensing combi appliance installation and maintenance instructions, 6 721 820 552 (2020/07).
Sections: 3.4 Appliance type overview; 6.5 Chimney sweep mode; 6.6 Checking gas inlet pressure; 6.7 Checking the gas rate; 6.9 CO and combustion check; 6.10 Checking flue integrity; 6.11 Flue gas analysis; 9.6 Flue gas analysis; 9.9 Setting the air/gas ratio; 13.1 Technical data.
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.