BoilerFaultCodesYour boiler's internal control board has become too hot and has shut down the system 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 fault
What causes this fault?
This fault occurs when the boiler's internal electronic control board reaches an unsafe operating temperature, triggering an automatic shutdown to prevent the components from melting or catching fire. The most common reason is a hardware failure within the circuitry of the main board or the display interface, though extreme external heat or poor ventilation around the boiler casing can also contribute.
This fault is more common during heatwaves in the summer, as high ambient temperatures make it harder for the boiler's internal electronics to stay within a safe operating range.
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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