BoilerFaultCodesYour boiler is struggling to control the amount of gas it uses, which prevents it from heating up correctly.
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 modulation fault
What causes this fault?
This fault occurs when the boiler's control board sends a command to the gas valve to adjust the flame size, but the valve fails to respond correctly. The most common reason is a mechanical failure within the gas valve itself or a communication breakdown in the wiring between the valve and the main circuit board.
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 F14 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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