BoilerFaultCodesYour boiler has shut down because a temperature sensor has detected that the burner area is getting 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: Burner thermostat has been activated.
What causes this fault?
This fault occurs when the safety sensor near the burner detects excessive heat that could potentially damage the internal components. The most common reasons are a buildup of debris or limescale inside the main heat exchanger restricting water flow, or a localized 'hot spot' caused by a failing internal thermostat. It acts as a critical safety shutdown to prevent the appliance from overheating.
This issue often surfaces in winter when the boiler is running at maximum capacity for long periods, putting the heat exchanger under the most thermal stress.
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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