BoilerFaultCodesTechnical description
Return sensor fault
What causes this fault?
This fault occurs when the internal sensor responsible for tracking the temperature of water entering the boiler fails to send a reliable signal. The most common reason is that the sensor has physically degraded over time or developed an electrical short, though loose or damaged wiring connections can also prevent the control board from reading the temperature accurately.
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.
Find a Gas Safe engineer
Search the official register →