Worcester Bosch Greenstar 1000 combi (GR1000W 24 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, case on, measured 10 minutes after firing, at the flue gas sample point. The technical data (MI 14.1) gives 9.0% for both sizes. | Between 8.6 and 9.4% |
CO₂ at low rate More infoHide infoBoiler at minimum in chimney sweep mode, case on, allowed to stabilise. The technical data (MI 14.1) gives 8.5% for both sizes, after 10 minutes. | A minimum of 0.5 lower than the maximum reading taken but above 8.1% |
Maximum CO More infoHide infoThe manual doesn’t agree with itself. The commissioning flow chart (MI 6.8, Fig. 68) uses CO < 350 ppm at maximum and minimum. The service table (MI 9.5, Table 32) gives <250 ppm at maximum and minimum. |
|
CO/CO₂ ratio More infoHide infoFrom the commissioning flow chart (MI 6.8, Fig. 68), at maximum and minimum. MI 6.6 refers to the technical data for CO/CO₂ ratios, but the technical data table doesn’t list one. | <0.004 |
O₂ | 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. The manual gives two different ranges for the gas valve inlet test point: 17–21.5 mbar in Table 25 and 16.0–20.5 mbar in Fig. 67 (both MI 6.5). At the meter: 20 mbar in Table 25, 18.5–23 mbar in Fig. 67. Allowed drop: 1 mbar across the pipework, 0.5 mbar across the appliance. |
|
Gas rate at maximum More infoHide infoMeasured at the meter after at least 10 minutes at maximum in service mode, with all other gas appliances off (MI 6.6). Figures from the technical data (MI 14.1). The output table for the 24 C (MI 14.5.1, Table 40) gives 43.4 l/min at 100%, which doesn’t match 2.47 m³/h. |
|
Flue integrity More infoHide infoAt the air inlet sample point on the flue turret/adaptor, case on, boiler at maximum in chimney sweep mode (MI 6.9). The text in 6.9 lists both readings, but the flow chart (Fig. 68) says O₂ ≥ 20.6% or CO₂ < 0.2%. | O₂ ≥ 20.6% CO₂ < 0.2% |
From 6721835943 (2023/08)
Enter service mode for high and low rate
High rate
- Hold the chimney sweep button (marked 5s) for at least 5 seconds until the chimney sweep symbol shows. MI 6.6 differs: it says press ok instead.
- It goes to maximum by itself. Display shows 100% and the flow temperature in turn.
Low rate
- Press ▼ for minimum. Display shows the minimum % and the flow temperature in turn.
- Press ▲ to go back to maximum.
- Press ↩ to come out (MI 6.6 says press ok instead). It also ends by itself after 30 minutes.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| GR1000W 24 C NG | 47-800-38 | NG |
| GR1000W 30 C NG | 47-800-39 | NG |
Source: Greenstar 1000 gas-fired condensing combi appliance installation and maintenance instructions, 6721835943 (2023/08).
Sections: 3.3 Appliance type overview; 6.4 Chimney sweep mode; 6.5 Checking gas inlet pressure; 6.6 Checking the gas rate; 6.8 CO and combustion check; 6.9 Checking flue integrity; 6.10 Flue gas analysis; 9.5 Flue gas analysis; 9.12 Setting the air/gas ratio; 14.1 Technical data; 14.5.1 Gas setting values (Natural Gas); 14.7 Inspection and maintenance checklist.
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.