BoilerFaultCodesTechnical description
Fault on Pump or Low System Pressure
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't circulating at the correct speed or pressure to safely carry heat away from the burner. The most common reasons are a drop in system pressure due to a minor leak, or a mechanical failure where the pump has seized or worn out over time.
This issue often surfaces in autumn when the heating is turned back on after summer, as pump components can seize during long periods of inactivity.
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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