BoilerFaultCodesTechnical description
Pre-circulation Fault
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the unit quickly enough before it attempts to ignite. The most common reason is a failing circulation pump or a blockage in the heat exchanger that prevents the flow of water. It can also be triggered by trapped air or a buildup of sludge within the system pipework.
This issue often surfaces when the heating is turned back on after the 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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