BoilerFaultCodesTechnical description
Diverter valve by Wilo
What causes this fault?
This fault occurs when the internal moving parts of the diverter valve become stuck or the motor that drives them fails to reach the correct position. This is often caused by a buildup of debris or sludge from the heating system water creating friction, which prevents the valve from switching between your heating and hot water.
This fault is more frequent in autumn when the heating is turned on for the first time after summer, as the valve may have seized during the long period 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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