BoilerFaultCodesTechnical description
Central heating return t° >90°C
What causes this fault?
This fault occurs when the water returning to the boiler is nearly boiling, which usually means the heat isn't being carried away to your radiators quickly enough. The most common reason is a failing pump that can't circulate the water, or a blockage in the system pipework that is restricting the flow.
This fault is more common when the heating is first turned on after summer, as circulation pumps can often seize up after 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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