BoilerFaultCodesYour boiler is failing to switch between providing hot water and heating, meaning your central heating may not turn on even when the system is calling for it.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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