BoilerFaultCodesTechnical description
Gas valve / Ionisation fault
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has been successfully lit or maintains an unstable signal. It is usually caused by a failure in the gas valve's ability to deliver fuel or a worn-out sensor that can no longer detect the heat from the burner. In some cases, the main circuit board may be misinterpreting these signals, leading the boiler to shut down for safety.
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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