BoilerFaultCodesTechnical description
Return sensor temperature exceeded
What causes this fault?
This fault occurs when the boiler detects that the water coming back from your heating system is at an unsafely high temperature. The most common reasons are a blockage in the pipes, a faulty pump that isn't moving water fast enough, or a sensor that has developed a technical fault and is giving a false reading.
This issue often appears at the start of winter when the heating is turned on for the first time after summer, as internal pump parts can seize during long periods of inactivity.
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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