BoilerFaultCodesTechnical description
Circulation
What causes this fault?
This fault occurs when the water inside the boiler is heating up too quickly because it isn't being pumped away fast enough. The most common reasons are a failed internal pump, a build-up of sludge blocking the pipes, or air trapped within the system that prevents smooth circulation.
This issue often surfaces in autumn when the heating is turned 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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