BoilerFaultCodesYour boiler has detected an internal electrical problem with the gas control valve, meaning it cannot safely ignite 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: Check gas valve wiring, if OK replace gas valve
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical connection with the gas valve or detects that the valve is not responding correctly. It is usually caused by a component failure within the gas valve itself or a faulty connection on the circuit board that prevents the boiler from safely controlling the flow of gas.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F16 — 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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