Ideal Checked against MI

Ideal Logic Max System² (S15, S18, S24, S30)

System boiler, natural gas

Combustion figures

Figure	Natural gas (G20)
CO₂ at high rate More infoHide info Table 1 gives these as CO₂ content at Max. CH, for the 15, 18, 24 and 30 kW boilers. The combustion is factory set: do not adjust the air/gas ratio valve.	S15 9.5% ± 0.7 S18 9.3% ± 0.7 S24 9.2% ± 0.7 S30 9.6% ± 0.7
CO₂ at low rate More infoHide info Table 1 gives these as CO₂ content at Min. CH.	S15 8.9% ± 0.7 S18 8.3% ± 0.7 S24 8.5% ± 0.7 S30 8.7% ± 0.7
Maximum CO More infoHide info At maximum and minimum rate, from the Benchmark CO and combustion ratio flowchart.	Less than 350 ppm
CO/CO₂ ratio More infoHide info At maximum and minimum rate, from the Benchmark flowchart. The servicing schedule (section 3.1) gives 0.004: above it, clean the boiler.	Less than 0.0040
O₂	Not given in MI
Working inlet pressure More infoHide info MI section 1.9 says a minimum operating pressure of 18 mb will be delivered to the appliance inlet, with a minimum meter outlet of 19 mb, and that the boiler can give full output at inlet pressures as low as 14 mb. Table 1 gives the gas supply as 2H-G20 - 20 mbar. Check at the gas cock test point with the boiler at maximum rate. The gas cock itself reduces the pressure measured at its test point, more so at higher heat inputs (graph in section 1.9).	Appliance inlet 18 mbar minimum
Gas rate at maximum More infoHide info Table 2 gas consumption at maximum, calculated at a calorific value of 38.7 MJ/m³ gross. Check at the gas meter with no other appliance in use.	S15 1.537 m³/h S18 1.872 m³/h S24 2.512 m³/h S30 3.136 m³/h
Flue integrity More infoHide info At the air inlet test point, boiler at maximum rate. The MI prints OR between the two figures.	O₂ ≥ 20.6% or CO₂ ≤ 0.2%

From UIN 228291 A06 (October 2022)

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 System² S15	41-796-97	NG
Logic Max System² S18	41-796-98	NG
Logic Max System² S24	41-796-99	NG
Logic Max System² S30	41-860-01	NG

Source: Ideal Logic Max System² S15 S18 S24 S30 Installation & Servicing, UIN 228291 A06 (October 2022).

Sections: 1.9 Gas supply; Table 1 General data; Table 2 Performance data; 2.24 Commissioning and testing; 2.25 Initial lighting; 2.29 Maximum and minimum rates; 2.30 General checks; 3.1 Servicing schedule; Section 6 Benchmark flowchart for CO level and combustion ratio check.

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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.