BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's control system detects that the internal temperature has exceeded safe limits or that water is not moving through the heat exchanger correctly. The most common reason is a failure in the communication between the temperature sensors or a pump that has seized and stopped circulating water. To prevent damage to the internal components, the boiler enters a protective shutdown mode.
This issue is more frequent during the first cold spell of autumn when pumps that have been idle all summer often struggle to restart or seize up.
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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