BoilerFaultCodesTechnical description
Diverter valve does not operate (CH test) / 230V at pin 3 of terminal X7 (Brown wire)
What causes this fault?
This fault occurs when the boiler's internal mechanism for switching between heating and hot water becomes stuck or fails to respond to electrical signals. The most common reason is that the motor responsible for moving the valve has burnt out, or the valve itself has become jammed with debris from the heating system's water.
This issue is most frequently noticed at the start of autumn when homeowners switch their heating back on for the first time after the summer months.
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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