BoilerFaultCodesTechnical description
No water in the boiler or the pump is not working
What causes this fault?
This fault occurs when the internal sensors detect that water isn't moving through the heat exchanger as it should, leading to a risk of overheating. The most common reasons are a pump that has seized or failed, a loss of system pressure, or a physical blockage like an air lock preventing flow.
This issue is more frequent in autumn when the heating is turned on for the first time after summer, as the pump can seize or stick during months 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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