BoilerFaultCodesTechnical description
Different temperature error
What causes this fault?
This fault occurs when the boiler detects a significant temperature gap between different sensors, which usually means water is trapped and overheating in one spot. The most common reasons are a failed pump that isn't moving the water or a blockage in the heat exchanger that is restricting flow. It can also be caused by a build-up of air or sludge within the system pipes.
This issue often appears when the heating is first turned on in autumn, as circulation pumps can seize up after being inactive throughout the 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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