BoilerFaultCodesTechnical description
Return temperature too high
What causes this fault?
This fault occurs when the water returning to the boiler is nearly as hot as the water leaving it, which prevents the heat from being transferred to your rooms. The most common reason is a blockage or a pump failure that stops water from circulating through your radiators, causing heat to build up inside the boiler unit itself.
This issue often appears when the heating is first turned on after summer, as internal pump parts can seize up 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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