BoilerFaultCodesYour boiler is struggling to light or keep its main flame burning steadily, which is preventing it from heating properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: failing or unstable flame of main burner
What causes this fault?
This fault occurs when the boiler's control system cannot detect a steady flame after trying to ignite the gas. The most common reasons are a worn-out sensing probe that can no longer see the flame, or a faulty gas valve that isn't providing the correct amount of fuel to keep the burner lit safely.
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.
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A boiler cover plan would cover faults like Green zone; end of green zone — 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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