Worcester Bosch Greenstar 2000 combi (GR2301iW 25 C, 30 C)
Combi, natural gas and LPG
Combustion figures
| Figure | Natural gas (G20) | LPG (G31) |
|---|---|---|
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 NG 9.4% (9.3% in its Low NOx column) and LPG 10.8%, for both sizes. | Between 9.0 and 10.8% | Between 10.6 and 11.0% |
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 NG 8.6% and LPG 10.2%, after 10 minutes. | A minimum of 0.6 lower than the maximum reading taken but above 8.2% | A minimum of 0.3 lower than the maximum reading taken but above 10.2% |
Maximum CO More infoHide infoThe manual doesn’t agree with itself. The commissioning flow chart (MI 6.9, Fig. 68) uses CO < 350 ppm at maximum and minimum. The service tables (MI 9.7, Tables 35 and 36) give <250 ppm at maximum and minimum. |
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CO/CO₂ ratio More infoHide infoFrom the commissioning flow chart (MI 6.9, Fig. 68), at maximum and minimum. MI 6.7 refers to the technical data for CO/CO₂ ratios, but the technical data tables don’t list one. | <0.004 | <0.004 |
O₂ | Not given in MI | Not given in MI |
Working inlet pressure More infoHide infoBoiler at maximum in chimney sweep mode, with heat taken away through the radiators and a hot tap. At the meter: NG 18.5–23 mbar. At the LPG storage: 32–45 mbar. Allowed drops: across the pipework NG 1 mbar, LPG 2.5 mbar; across the appliance 1.5 mbar; LPG storage to regulator 0.5 mbar. |
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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. Where there’s no meter (e.g. LPG), check CO/CO₂ instead (MI 6.7). The LPG figures are printed with the unit kg/m³, which looks like a misprint in the MI. |
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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. 68) says O₂ ≥ 20.6% or CO₂ < 0.2%. | O₂ ≥ 20.6% CO₂ < 0.2% | O₂ ≥ 20.6% CO₂ < 0.2% |
From 6721839340 (2023/06)
Enter service mode for high and low rate
High rate
- Hold ok for at least 5 seconds. The chimney sweep symbol shows on the display.
- 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 |
|---|---|---|
| GR2301iW 25 C NG | 47-800-34 | NG |
| GR2301iW 30 C NG | 47-800-36 | NG |
| GR2301iW 25 C LPG | 47-800-35 | LPG |
| GR2301iW 30 C LPG | 47-800-37 | LPG |
Source: Greenstar 2000 gas-fired condensing combi appliance installation and maintenance instructions, 6721839340 (2023/06).
Sections: 3.5 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; 9.7 Flue gas analysis; 9.10 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.