BoilerFaultCodesYour boiler's main control board hasn't been set up correctly to tell it which model it is, so it doesn't know how to operate yet.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Display shows F9 on power on (Unprogrammed PCB)
What causes this fault?
This fault occurs when the boiler's internal computer brain is blank and hasn't been told which specific model it is installed in. This usually happens because a new part was recently fitted but not configured, or because a sudden electrical glitch has caused the memory to wipe itself.
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 F9 — no call-out fees, no surprises.
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Ideal Logic Combi ESP1 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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