Glow-worm Flexicom hx (12hx, 15hx, 18hx, 24hx, 30hx, 35hx)
Heat only (open vented or sealed system), natural gas
Combustion figures
| Figure | Natural gas (G20) |
|---|---|
CO₂ at high rate More infoHide infoOne table for all models (G20 burner % CO₂, section 13). Wait until the CO₂ value is stable. Adjust only if outside the check range, then set within the setting limits. The boiler specification (section 1, diagram 1.2) gives burner CO₂ as 9.3 nominal, case on and case off. |
|
CO₂ at low rate More infoHide infoThe MI uses the same check and setting columns for maximum and minimum rate. Adjustment at minimum is very coarse: no more than 1/8 of a turn at a time, waiting 1 minute between adjustments. |
|
Maximum CO | Not given in MI |
CO/CO₂ ratio More infoHide infoMust not exceed this value. Re-check after setting CO₂ at maximum and minimum. | 0.004 |
O₂ | Not given in MI |
Working inlet pressure More infoHide infoNominal supply pressure, checked at the gas service isolation valve test point with all other gas appliances operating and the boiler forced to maximum. The MI adds that the safe nominal maximum heat input can be achieved at an inlet pressure down to 15 mbar. |
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Gas rate at maximum More infoHide infoApproximate, natural gas G20, checked at the meter at least 10 minutes after the burner has lit. The boiler specification gives approximate minimum gas rate as 0.99 m³/h for all models. If the boiler has been range rated, section 12.6 gives the gas rate for each kW setting from 10 to 35 kW. |
|
From 0020057279-04 01.10
Enter service mode for high and low rate
High rate
Steps not added yet. Follow the MI.
Low rate
Steps not added yet. Follow the MI.
Ending the test: follow the MI.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| Flexicom 12hx | 41-315-28 | NG |
| Flexicom 15hx | 41-315-29 | NG |
| Flexicom 18hx | 41-315-42 | NG |
| Flexicom 24hx | 41-315-61 | NG |
| Flexicom 30hx | 41-315-67 | NG |
| Flexicom 35hx | 41-315-68 | NG |
Source: Glow-worm Flexicom Installation and Servicing (12hx, 15hx, 18hx, 24hx, 30hx, 35hx), 0020057279-04 01.10.
Sections: 1 Boiler Specification (diagram 1.2); 12.3 Gas Supply; 12.5 Check the Gas Inlet Pressure & Gas Rate; 12.6 Range Rating; 13 Servicing: Combustion check and setting the air/gas ratio valve (maximum and minimum rate check and adjustment, re-check CO2 and CO/CO2 ratio).
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.