Your boiler has detected that the gas valve is not closing as quickly as it should, preventing the unit from shutting down safely and causing it to lock out.
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 shut-off delay fault
What causes this fault?
This fault occurs when the boiler's internal computer detects that the gas valve is failing to shut off properly after the flame should have extinguished. The most common reason is a mechanical stickiness within the gas valve itself or a failure in the main control board's electronics that incorrectly tells the valve to stay open.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F.62 — no call-out fees, no surprises.
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