Ideal Icos HE36 Fault codes & diagnostics

4 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Natural Gas 2006-2011 Discontinued
GC Number 41-399-16
Download the Ideal Icos HE36 manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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All 4 documented codes

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H9

Your boiler has detected that the gases it is producing are significantly hotter than they should be, so it has shut itself down to prevent damage or overheating.

High Engineer only £150-300

Parts commonly replaced

  • Flue gas thermistor
  • Primary heat exchanger
  • Pump

Related codes

L : F

Your boiler has tried to light up several times but has failed to start, so it has safely shut itself down.

High Engineer only £150-£300

Parts commonly replaced

  • Ignition lead
  • Spark electrode
  • Gas valve

Related codes

L-F

Your boiler has stopped working because it tried to ignite but failed to detect a steady flame.

High Engineer only £150-300

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

L9

Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent damage or fire risk.

Emergency Engineer only £150-300

Parts commonly replaced

  • Heat exchanger
  • Flue sensor
  • Pump