Worcester Bosch Greenstar 8000 Life system (GR8300iW 30 S, 35 S)
System boiler, 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. Measure 10 minutes after firing, with the combustion chamber cover on. | 9.5% ± 0.4 | 10.8% ± 0.4 |
CO₂ at low rate More infoHide infoBoiler at minimum in chimney sweep mode. Measure 10 minutes after firing, with the combustion chamber cover on. | 8.6% ± 0.4 | 10.2% ± 0.4 |
Maximum CO More infoHide infoThe manual contradicts itself. Tables 26 and 27 (MI 8.7 and 8.10) give under 250 ppm at maximum and under 75 ppm at minimum, and MI 8.10.1 also says CO must be under 250 ppm. The commissioning checks flow chart (Fig. 66, MI 6.10) uses CO under 350 ppm at both maximum and minimum. |
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CO/CO₂ ratio More infoHide infoFrom the commissioning checks flow chart (Fig. 66, MI 6.10), at maximum and minimum rate. MI 6.8 refers to the technical data for CO/CO₂ ratios, but the technical data table (Table 30) doesn’t give one. | < 0.004 | < 0.004 |
O₂ at high rate More infoHide infoNo tolerance given. | 4.0% | 4.6% |
O₂ at low rate More infoHide infoFrom Tables 26 and 27. No tolerance given. | 5.5% | 5.5% |
Working inlet pressure More infoHide infoAt the meter: NG 19–23 mbar. At the LPG supply (storage): 32–45 mbar. Checked with the boiler at maximum in chimney sweep mode. Maximum drop from the meter or LPG supply to the gas valve inlet test point: 2.5 mbar NG, 4 mbar LPG. |
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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, with all other gas appliances off. The NG rate assumes an average calorific value printed as 34-9 MJ/m³ net. |
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Flue integrity More infoHide infoAt the air inlet sample point on the flue turret or adaptor, combustion casing on, boiler at maximum in chimney sweep mode. Readings outside these limits mean a problem with the flue system or combustion circuit. | O₂ ≥ 20.6% CO₂ < 0.2% | O₂ ≥ 20.6% CO₂ < 0.2% |
From 6720883858 (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. It also returns to normal operation by itself after 15 minutes.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| GR8300iW 30 S NG | 41-406-91 | NG |
| GR8300iW 35 S NG | 41-406-90 | NG |
| GR8300iW 30 S LPG | 41-406-93 | LPG |
| GR8300iW 35 S LPG | 41-406-92 | LPG |
Source: Worcester Greenstar 8000 Life gas fired condensing system boiler (GR8300iW 30 S, 35 S) installation and maintenance instructions, 6720883858 (2019/02).
Sections: 3.5 Appliance type overview; 6.4 Chimney sweep mode; 6.7 Checking gas inlet pressure; 6.8 Checking the gas rate; 6.10 CO and combustion check; 6.11 Checking flue integrity; 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.