BoilerFaultCodesYour boiler's internal control board has become too hot and has shut itself down to prevent damage.
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 computer chips reach a temperature that is high enough to risk permanent damage. The most common reason is that heat is escaping from the local combustion area and soaking into the surrounding electronics, often due to degraded insulation or poor ventilation inside the casing.
This fault can be more prevalent during heatwaves or hot summer weather, as the higher ambient air temperature makes it harder for the boiler's internal components to cool down.
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.65 — 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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