BoilerFaultCodesTechnical description
OVERHEAT
What causes this fault?
This fault occurs when the internal temperature of the boiler exceeds a safe limit, causing the safety sensors to shut the system down instantly. The most common reason is that the water isn't moving through the unit quickly enough to carry the heat away, often due to a failed pump or a build-up of sludge blocking the pipes. In some cases, a faulty sensor may also be misreading the temperature and triggering a false alarm.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on and a pump that has been idle all summer fails to start.
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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