BoilerFaultCodesYour boiler is struggling to circulate water effectively because the internal pump is not running at the correct speed.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Pump speed
What causes this fault?
This fault occurs when the boiler's control board sends a signal to the internal pump to change speed, but the pump fails to respond or reach the required velocity. The most common reason is that the pump has become seized due to debris in the heating system or the electrical communication cable between the board and the pump has developed a fault.
This issue is more frequent in autumn when the heating is turned back on after a long summer break, as the pump can seize up from lack of movement.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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