BoilerFaultCodesYour boiler has detected a problem with the internal gas valve and has shut down as a safety precaution, meaning you will have no heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas safety value failure
What causes this fault?
This fault occurs when the boiler's main control board detects an electrical failure or a mechanical blockage within the gas valve assembly. The most common reason is that the valve's internal solenoid has burnt out or is no longer communicating correctly with the electronics, preventing gas from safely entering the burner.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 16 — no call-out fees, no surprises.
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