BoilerFaultCodesTechnical description
Sensor fault, flow temperature increasing too fast in heating mode or insufficient circulation.
What causes this fault?
This fault occurs when the water inside your boiler heats up too quickly because it isn't being pumped away and into your radiators fast enough. The most common reasons are a pump that has seized up or a build-up of sludge and debris in the system that is restricting the flow of water.
This fault is more frequent in autumn when the heating is turned back on after a long summer break, as internal pump parts can seize up from lack of use.
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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