BoilerFaultCodesTechnical description
Flow and/or return sensor fault
What causes this fault?
This fault occurs when the sensors that monitor the water temperature leaving and returning to your boiler provide inconsistent or impossible readings. The most common reason is that one of these sensors has physically degraded or failed over time, preventing the boiler from safely knowing how hot the water actually is. In some cases, it can also be triggered by a fault in the internal wiring that connects these sensors to the main control board.
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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