BoilerFaultCodesTechnical description
Overheat/Limit thermostat or burner thermostat (35e only) fault
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, triggering a safety sensor to cut the power. The most common reasons are a pump failure preventing heat from being moved away from the boiler, or a blockage in the pipework restricting flow. In some cases, the overheat sensor itself may have become faulty and is reporting a high temperature even if the water is cool.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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