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Ideal Checked against MI

Ideal Logic Heat (12, 15, 18, 24, 30)

Heat only (regular), natural gas

Combustion figures

FigureNatural gas (G20)
CO₂ at high rate
More infoHide infoThe MI says combustion is factory set and the air/gas ratio valve must not be adjusted. It asks for CO and CO/CO₂ ratio checks only, with no CO₂ figure.
Not given in MI
CO₂ at low rate
Not given in MI
Maximum CO
More infoHide infoAt maximum and at minimum rate, analyser probe in the flue gas sampling point, readings allowed to stabilise (commissioning flowchart).
Less than 350 ppm
CO/CO₂ ratio
More infoHide infoAt maximum and at minimum rate (commissioning flowchart). The servicing schedule says to contact Ideal if the ratio is greater than 0.004 after the flue, seals, inlet pressure and gas rate have been checked.
Less than 0.0040
O₂
Not given in MI
Working inlet pressure
More infoHide infoChecked at the inlet pressure test point on the gas service cock with the boiler at maximum rate. The MI says the boiler can give full output at inlet pressures as low as 14 mbar, and that the minimum meter outlet pressure is 19 mbar. Table 1 gives the gas supply as 2H – G20 – 20 mbar.
Appliance inlet
18 mbar minimum
Gas rate at maximum
More infoHide infoGas consumption from Table 2, calculated at a gross CV of 38.7 MJ/m³. Check at the gas meter with no other appliance in use.
12
1.246 m³/h
15
1.537 m³/h
18
1.872 m³/h
24
2.512 m³/h
30
3.135 m³/h
Flue integrity
More infoHide infoAt the air inlet test point (where available), boiler at maximum rate. If not met, investigate the flue.
O₂ ≥ 20.6% or CO₂ ≤ 0.2%

From UIN 205862 A06 (January 2014)

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
Logic Heat 1241-399-99NG
Logic Heat 1541-409-93NG
Logic Heat 1841-409-94NG
Logic Heat 2441-409-95NG
Logic Heat 3041-409-96NG

Source: Ideal Logic Heat 12, 15, 18, 24, 30 Installation and Servicing, UIN 205862 A06 (January 2014).

Sections: Table 1 General data; Table 2 Performance data; Gas supply (p. 8); 40 Commissioning and testing; 41 Initial lighting; 42 General checks; 45 Servicing schedule; Flowchart for CO level and combustion ratio check (pp. 60–61).

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.