BoilerFaultCodesYour boiler has detected a problem with how it controls the gas supply, meaning it cannot safely light the flame to provide 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 valve fault
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the gas valve or detects an electrical mismatch during the ignition process. It is typically caused by a mechanical failure within the valve itself or a faulty connection in the internal wiring that prevents the boiler from safely managing the fuel flow.
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 F.88 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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