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 the flames ignite. The most common reasons are a seized central heating pump that can't push the water around, or a build-up of sludge and debris creating a physical blockage in the heat exchanger.
This issue often appears at the start of autumn when the heating is turned back on after being idle all summer, which can cause the pump to stick.
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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