BoilerFaultCodesYour boiler has shut down because a safety sensor detected that a internal component has become too hot.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Appears if the burner thermostat has been activated.
What causes this fault?
This fault occurs when a safety sensor near the burner detects that the internal temperature has exceeded safe limits, causing the boiler to shut down to prevent damage. The most common reason is a build-up of debris or limescale inside the heat exchanger which restricts water flow, but it can also be caused by a faulty sensor or a pump failure.
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.
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A boiler cover plan would cover faults like 08 — no call-out fees, no surprises.
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