BoilerFaultCodesYour boiler is unable to release gas into the burner because the internal electronic valve is not operating correctly, meaning it cannot ignite to provide heat 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: Fault: Fuel valve not working - Gas valve assembly stepper motor defective or not connected
What causes this fault?
This fault occurs when the boiler's main control board tries to open the gas valve to start the heating process, but it receives no response from the valve's motor. The most common reason is that the internal electronic components of the gas valve have failed, or the wiring connecting it to the computer has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.26 — 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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