BoilerFaultCodesWhat the manual says
Manufacturer manualOverheating fault
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the water inside the boiler gets too hot, causing a safety sensor to trip and shut the system down. The most common reasons are a pump failure that stops water from circulating or a buildup of sludge and debris that restricts flow through the heat exchanger.
This fault is more common when the heating is first turned on in autumn, as pump components can seize up after being idle throughout the summer.
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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