BoilerFaultCodesYour boiler is failing to keep the pilot light burning after you let go of the ignition button, meaning the heating cannot start.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PILOT WILL NOT STAY LIT WHEN THE GAS CONTROL VALVE KNOB IS RELEASED
What causes this fault?
This fault occurs when the boiler's safety monitoring system fails to detect a stable flame after the lighting process. The most common reason is a worn-out thermocouple that can no longer send a signal to the gas valve, or the overheat thermostat has tripped and cut the internal circuit to prevent damage. Essentially, the boiler shuts down the gas supply because it believes it is unsafe to stay running.
This issue often surfaces during the first cold spell of autumn when the boiler is switched back on after being idle during the summer months.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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