Flame On Before Gas Valve On High

Ideal Flame On Before Gas Valve On Fault Code

Also written as FLAMEONBEFOREGASVALVEON — same fault.

The Ideal Flame On Before Gas Valve On fault code means: your boiler's safety system has detected a flame signal when there shouldn't be one, which prevents the unit from starting up for safety reasons.. It appears on 5 Ideal models in our database.

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.

Technical description: Internal boiler wiring integrity issue or deteriorated electrode causing flame signal before gas valve activation.

What causes the Ideal Flame On Before Gas Valve On fault?

This fault occurs when the boiler's control system detects an electrical current that mimics a flame before the gas valve has even opened. The most common reason is a buildup of carbon or moisture on the sensing electrode that allows electricity to 'leak', or a fault within the main circuit board that is misreading signals. Because the boiler thinks a flame is already present, it shuts down immediately as a safety precaution to prevent gas from being released incorrectly.

This issue can be more common during periods of high humidity or very cold weather, as moisture or condensation inside the boiler casing can interfere with the sensitive electrical signals of the ignition system.

Typical repair cost £120-£280 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ideal models that show the Flame On Before Gas Valve On fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ideal Flame On Before Gas Valve On fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026