BoilerFaultCodesTechnical description
Limit thermostat fault
What causes this fault?
This fault occurs when the boiler's control system tries to start the burner but cannot detect a flame after several attempts. The most common reason is a lack of gas reaching the burner or a failure in the ignition system that prevents the spark from creating a steady fire. It can also be caused by worn-out sensors that fail to tell the boiler that a flame is actually present.
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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