BoilerFaultCodesTechnical description
Pre-Circulation Fault
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't flowing through the heat exchanger as fast as it should. The most common reasons are a failed or sticking pump, air trapped within the system, or a blockage caused by a buildup of sludge and debris.
This issue is more frequent in autumn when the heating is turned on for the first time after summer, as pumps 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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