BoilerFaultCodesTechnical description
Problem with the pump circulation
What causes this fault?
This fault occurs when the boiler detects that water is not moving through the heat exchanger quickly enough, leading to a rapid rise in temperature. The most common cause is a seized or failing circulation pump, though it can also be triggered by a build-up of sludge or debris blocking the internal pipework. In some cases, a faulty control board may simply be failing to send power to the pump to start the cycle.
This issue is more frequent in autumn when heating systems are switched back on after being idle all summer, which often causes internal pump components to stick.
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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