BoilerFaultCodesYour boiler's computer brain has encountered a serious communication error and can no longer control the heating system safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main board fault
What causes this fault?
This fault occurs when the boiler's internal computer experiences a major electrical short or a critical component failure on the control board. The most common reason is general wear and tear of the electrical circuits over time, or pulse damage caused by a power surge.
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 F13 — no call-out fees, no surprises.
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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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