BoilerFaultCodesTechnical description
No Water Flow
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the unit quickly enough to safely carry heat away. The most common reasons are a seized internal pump, a significant blockage in the pipework, or a faulty sensor providing an incorrect reading to the control board.
This issue often surfaces during the first cold spell of autumn when a pump that has been sitting idle all summer fails to restart.
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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