BoilerFaultCodesYour boiler's safety sensor has detected that the main heating component is getting too hot, so the system 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: Overheating protection on the primary heat exchanger has triggered
What causes this fault?
This fault occurs when a dedicated safety fuse inside the boiler melts because the main heat exchanger has reached a dangerously high temperature. It is usually caused by a lack of water flow, a severe internal blockage, or the buildup of debris that prevents the system from cooling itself down properly. This is a critical safety shutdown designed to prevent the metal components from warping or cracking.
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.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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