BoilerFaultCodesTechnical description
Overheat cut off device tripped or thermostat, overheat cut off device faulty
What causes this fault?
This fault occurs when the water inside the boiler gets too hot, causing a safety switch to trip and shut the system down to prevent damage. The most common reasons are a pump failure that stops water from moving or a buildup of debris that blocks the flow, but it can also be caused by a sensor that has simply become faulty over time.
This issue is more frequent when you first switch your heating on for the winter, as pumps can seize up after being inactive throughout the summer months.
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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