High
Flame On Before Gas On on Ideal Logic Max Heat

Your boiler incorrectly thinks it sees a flame before it has even started the ignition process, which is a safety error that prevents it from starting up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

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From this model's manual
Verified against the Ideal Logic Max Heat installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's control system detects an electrical signal suggesting a flame is already present before the gas has been turned on. The most common reason is a carbon build-up or moisture on the sensing electrode causing a false reading, or a communication error within the main circuit board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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