BoilerFaultCodesYour boiler has shut down because its internal electrical components have become too hot and need to cool down.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Electronics temperature too high
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the main control board has reached a dangerously high temperature. It is usually caused by excessive heat building up inside the boiler casing, often due to a component failure or a loose electrical connection causing a short. To prevent permanent damage to the electronics, the system shuts down automatically to allow everything to cool over time.
This fault can be more common during heatwaves or in very small, unventilated cupboards where the ambient air temperature prevents the boiler from cooling itself effectively.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.85 — 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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