BoilerFaultCodesTechnical description
Limit thermostat fault
What causes this fault?
This fault occurs when the water inside the boiler gets too hot, causing a safety sensor to trip and shut the system down to prevent internal damage. The most common reasons are a lack of water flow due to a failing pump, a blockage in the heat exchanger, or a buildup of air within the pipes.
This issue is more common during the first few cold days of autumn when a pump that has been idle all summer suddenly seizes up upon being restarted.
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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