BoilerFaultCodesYour boiler is failing to light the gas flame properly, meaning 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 ionisation after ignition phase, defective igniter / fan is not rotating / igniter and fan are functioning.
What causes this fault?
This fault occurs when the boiler's control system tries to start the burner but cannot detect a stable flame. It is usually caused by a blockage in the burners, a worn-out ignition spark, or a failed sensor that cannot 'see' the fire once it has lit. In some cases, it may also happen because the internal fan isn't spinning fast enough to clear out old gases and allow fresh air in for combustion.
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 6A — no call-out fees, no surprises.
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Ideal Maximiser SE 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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