BoilerFaultCodesTechnical description
Pump flow error
What causes this fault?
This fault occurs when the boiler detects that water is not circulating through the heat exchanger quickly enough to safely carry heat away. The most common reasons are a seized or failing internal pump, a blockage caused by sludge buildup, or air trapped within the pipework. Because the system cannot move the hot water out, it shuts down to prevent the internal components from overheating and sustaining damage.
This issue is more frequent during the first cold snap of autumn when a pump that has sat idle all summer struggles to start spinning again.
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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