BoilerFaultCodesTechnical description
Return temperature sensor failed
What causes this fault?
This fault occurs when the internal electronic sensor responsible for monitoring the water coming back into the boiler becomes damaged or loses its connection. Over time, heat stress or moisture can cause the sensor to degrade, preventing it from sending a reliable signal to the main control board. Without this vital temperature data, the boiler shuts down as a safety precaution to prevent internal overheating.
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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