Ideal Checked against MI

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

Heat only (regular), natural gas

Combustion figures

Figure	Natural gas (G20)
CO₂ at high rate More infoHide info Table 1 CO₂ content (± 0.7), Max. CH. The MI gives no timing or case on/off condition here; the flowchart says to let readings stabilise before recording. The air/gas ratio valve is factory set and must not be adjusted during commissioning.	12 9.1% ± 0.7 15, 30 9.3% ± 0.7 18, 24 9.5% ± 0.7
CO₂ at low rate More infoHide info Table 1 CO₂ content (± 0.7), Min. CH.	12 8.5% ± 0.7 15, 24, 30 8.8% ± 0.7 18 8.9% ± 0.7
Maximum CO More infoHide info At maximum and minimum rate (commissioning flowchart, MI p. 67).	Less than 350 ppm
CO/CO₂ ratio More infoHide info At maximum and minimum rate (commissioning flowchart, MI p. 67). Section 3.1 Servicing schedule gives the same limit as 0.004: above it, carry out the cleaning procedure.	Less than 0.0040
O₂	Not given in MI
Working inlet pressure More infoHide info Section 1.8: minimum permitted operating pressure of 18 mb at the appliance inlet, allowing 1 mb loss from a minimum meter outlet of 19 mb. Checked at maximum rate at the inlet pressure test point on the gas service cock. Table 1 gives the gas supply as 2H - G20 - 20 mbar. The MI also says the boiler can deliver full output at inlet pressures as low as 14 mb, and that the gas cock reduces the pressure measured at its test point (graph in Section 1.8).	Appliance inlet 18 mbar minimum
Gas rate at maximum More infoHide info Table 2 gas consumption at maximum input. Calculated using a calorific value of 38.7 MJ/m³ gross. 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 info At the air inlet test point, boiler at maximum rate. Where no air inlet test point is provided, check the flue visually instead.	O₂ ≥ 20.6% or CO₂ ≤ 0.2%

From UIN 219010 A04 (February 2019)

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
Logic Max Heat H 12	41-796-17	NG
Logic Max Heat H 15	41-796-18	NG
Logic Max Heat H 18	41-796-19	NG
Logic Max Heat H 24	41-796-20	NG
Logic Max Heat H 30	41-796-21	NG

Source: Ideal Logic Max Heat H 12 15 18 24 30 Installation & Servicing, UIN 219010 A04 (February 2019).

Sections: Table 1 General data; Table 2 Performance data; 1.8 Gas supply; 2.25 Commissioning and testing; 2.27 General checks; 3.1 Servicing schedule; Flowchart for CO level and combustion ratio check (setting to maximum and minimum rate).

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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.