BoilerFaultCodesYour boiler has shut down because a safety sensor has detected that the main component which heats your water has reached a dangerously high temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheating protection on the primary heat exchanger has responded
What causes this fault?
This fault occurs when the heating element inside your boiler gets too hot, causing a safety fuse to blow to prevent damage or fire. The most common reasons are a build-up of debris or sludge blocking the flow of water, or a failure of the internal pump that circulates heat away from the burner.
This issue often surfaces when you first turn the heating back on in autumn, as debris that settled over the summer can shift and block the system.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F.76 — 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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