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Glow-worm Checked against MI

Glow-worm Ultimate 3 system (25s)

System boiler, natural gas

Combustion figures

FigureNatural gas (G20)
CO₂ at high rate
More infoHide infoCheck programme P.01 set to 100, wait 5 minutes for a stable reading, measured at the flue gas analysis point. The MI gives two tolerances: ±1 % in the Checking the CO₂ content tables (7.9.5 and 11.3), and ±0.2 % in the Setting the CO₂ value table (11.4), which also says CO₂ at full load. The tables are headed Removed front casing/installed front casing, but 11.4 says to set the value with the front casing removed.
Setting
9.2 ±0.2 %
Check
9.2 ±1 %
CO₂ at low rate
Not given in MI
Maximum CO
More infoHide infoThe setting table (11.4) gives CO at full load ≤ 250 ppm. The combustion chart (Appendix I) gives CO less than 350 ppm at both maximum and minimum rate, and less than 335 ppm on the recheck after checking the seals. Both are printed in the MI.
Setting table
≤ 250 ppm
Combustion chart
< 350 ppm
CO/CO₂ ratio
More infoHide infoThe setting table (11.4) gives ≤ 0.0027 at full load. The combustion chart (Appendix I) gives less than 0.004 at both maximum and minimum rate.
Setting table
≤ 0.0027
Combustion chart
< 0.004
O₂ at high rate
More infoHide infoO₂ at full load, from the Setting the CO₂ value table (11.4).
4.5 ±1.8 vol. %
O₂ at low rate
Not given in MI
Working inlet pressure
More infoHide infoMeasured at the measuring nipple on the gas isolator cock with the boiler at full load (check programme P.01, or P.03 without an eBUS controller). Technical data gives G20 gas supply pressure as 20 mbar.
Appliance inlet
17.0–20 mbar
Gas rate at maximum
More infoHide infoHot water maximum (Q max. hot water 30.6 kW). Technical data gives gas flow at P max. hot water (G20) as 3.2 m³/h; the 7.9.1 table gives 3.24 m³/h nominal for Qnw 30.6. Measured at the gas meter with check programme P.01, front casing fitted, after at least 5 minutes, with all other gas appliances off.
Technical data
3.2 m³/h
Gas flow table
3.24 m³/h (+5%: 3.40, −10%: 2.92)
Flue integrity
More infoHide infoAt the air analysis (air inlet) point with the boiler at maximum rate, from the combustion chart (Appendix I) and 7.9.3.
O₂ ≥ 20.6%
CO₂ < 0.2%

From 0020239564_01 &ndash; 10.10.2016

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

ModelGC numberGas
Ultimate 3 25s41-019-51NG

Source: Glow-worm Ultimate 3 25s installation and maintenance instructions, 0020239564_01 &ndash; 10.10.2016.

Sections: 2.3 Applicability of the instructions; 7.9.1 Checking the gas flow rate; 7.9.2 Checking the gas connection pressure; 7.9.3 Checking the leak-tightness of the flue gas installation; 7.9.5 Checking the CO2 content; 11.3 Checking the CO2 content; 11.4 Setting the CO2 content; A Check programmes; I Combustion chart; K 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.