BoilerFaultCodesTechnical description
Primary circulation fault or pump failure
What causes this fault?
This fault occurs when the water inside the boiler gets too hot too quickly because it isn't being pushed away into your radiators or hot water tank. The most common reason is that the internal pump has failed or is physically jammed, but it can also be caused by a build-up of sludge blocking the pipework or an airlock trapped in the system.
This issue is frequently seen in autumn when heating systems are switched back on after being idle all summer, which can cause the pump to seize.
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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