BoilerFaultCodesYour boiler has failed to ignite or stay lit correctly, meaning it cannot provide heating or hot water until it is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault burner
What causes this fault?
This fault occurs when the boiler's control system cannot detect a steady flame after trying to ignite. The most common reasons are a worn-out sensor that monitors the flame, a build-up of carbon on the sparking electrodes, or a fault with the gas valve that prevents fuel from reaching the burner.
This fault is frequently seen during the first cold snap of autumn when internal components that have been idle over summer fail to operate correctly under increased demand.
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 G5 — no call-out fees, no surprises.
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Worcester Bosch WR325 RSF is discontinued — time for a new one?
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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