BoilerFaultCodesTechnical description
3-way valve
What causes this fault?
This fault occurs when the mechanical component that directs hot water between your taps and radiators becomes jammed or fails to move. It is often caused by a build-up of debris and sludge from within the heating system or a simple failure of the small motor that pushes the valve into position.
This issue is frequently noticed in autumn when homeowners turn their heating back on for the first time, as the valve may have seized after months of only providing hot water.
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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