BoilerFaultCodesYour boiler is failing to light the main burner, which means it cannot heat your water or radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: no flame (signal) of main burner
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner but fails to detect a steady flame. It is usually caused by worn-out ignition components that can no longer create a spark or a faulty sensor that cannot tell the boiler the flame is actually lit.
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 end of yellow zone; begin 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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