Worcester Bosch Greenstar 8000 Life combi (GR8300iW 30 C, 35 C, 40 C, 45 C, 50 C)
Combi, natural gas and LPG
Combustion figures
| Figure | Natural gas (G20) | LPG (G31) |
|---|---|---|
CO₂ at high rate More infoHide infoMeasured 10 minutes after firing, combustion cover on, at the flue gas sample point on the flue turret/adaptor, boiler at maximum in chimney sweep mode. | 9.5% ± 0.4 | 10.8% ± 0.4 |
CO₂ at low rate More infoHide infoMeasured 10 minutes after firing, combustion cover on, boiler at minimum in chimney sweep mode. | 8.6% ± 0.4 | 10.2% ± 0.4 |
Maximum CO More infoHide infoThe MI gives two limits. Tables 26 and 27 (MI 8.7 and 8.10) give <250 ppm at maximum and <75 ppm at minimum, and 8.10.1 says CO must be <250 ppm. The commissioning flow chart (MI 6.9, Fig. 66) uses CO <350 ppm as the pass limit at both maximum and minimum rate. The MI doesn’t explain the difference. |
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CO/CO₂ ratio More infoHide infoFrom the commissioning flow chart (MI 6.9, Fig. 66), at maximum and minimum rate. MI 6.7 refers to the technical data for CO/CO₂ ratios, but the technical data doesn’t give any. | < 0.004 | < 0.004 |
O₂ at high rate More infoHide infoNo tolerance given. | 4.0% | 4.6% |
O₂ at low rate More infoHide infoAt minimum rated output. No tolerance given. | 5.5% | 5.5% |
Working inlet pressure More infoHide infoBoiler at maximum in chimney sweep mode. At the meter: NG 19–23 mbar. At the LPG supply: 32–45 mbar. The MI splits the gas valve figure by ≤ 40 kW and > 40 kW without naming models. The model names give hot water output in kW (MI 3.5), but the technical data gives the 40 C a DHW output of 40.8 kW. The MI text also says the LPG drop from supply to gas valve must not be more than 4 mbar, while Table 16 allows up to 5 mbar for > 40 kW. |
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Gas rate at maximum More infoHide info10 minutes from lighting. Measure at the gas meter after at least 10 minutes at maximum in chimney sweep mode, with all other gas appliances off. Running a hot tap doesn’t guarantee maximum output. Where there’s no gas meter (e.g. LPG), the MI says check CO/CO₂ instead. |
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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, readings allowed to settle. Readings outside these limits indicate a problem with the flue system or combustion circuit. | O₂ ≥ 20.6% CO₂ < 0.2% | O₂ ≥ 20.6% CO₂ < 0.2% |
From 6720883865 (2019/02)
Enter service mode for high and low rate
High rate
- Hold ok for 5 seconds until the countdown finishes and the chimney sweep symbol shows.
- Use ▲ to set maximum. The value is accepted after 2 seconds.
Low rate
- Use ▼ to set minimum. The value is accepted after 2 seconds.
- Use ▲ to go back to maximum.
Ending the test
- Press ↩ to come out. MI 6.7 says ok also works.
- It ends by itself after 15 minutes.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| GR8300iW 30 C NG | 47-800-18 | NG |
| GR8300iW 35 C NG | 47-800-17 | NG |
| GR8300iW 40 C NG | 47-800-16 | NG |
| GR8300iW 45 C NG | 47-800-15 | NG |
| GR8300iW 50 C NG | 47-800-14 | NG |
| GR8300iW 30 C LPG | 47-800-23 | LPG |
| GR8300iW 35 C LPG | 47-800-22 | LPG |
| GR8300iW 40 C LPG | 47-800-21 | LPG |
| GR8300iW 45 C LPG | 47-800-20 | LPG |
| GR8300iW 50 C LPG | 47-800-19 | LPG |
Source: Worcester Greenstar 8000 Life (GR8300iW C) installation and maintenance instructions, 6720883865 (2019/02).
Sections: 3.5 Appliance type overview; 6.4 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; 8.7 Flue gas analysis; 8.10 Setting the air/gas ratio; 12.1 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.