BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal safety switches detect that the water temperature has exceeded safe operating limits. The most common cause is a lack of water circulation, often due to a failing pump or a blockage within the heat exchanger. Because the heat cannot be moved away from the burner quickly enough, the system shuts down to prevent permanent damage to the components.
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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