BoilerFaultCodesTechnical description
Limit thermostat fault
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature, triggering a safety switch to shut the system down. The most common reasons are a pump that has stopped moving water around the system or a blockage in the heat exchanger that prevents heat from escaping.
This fault is more frequent when you first turn the heating back on in autumn, as circulating pumps often seize up after being inactive all summer.
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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