BoilerFaultCodesTechnical description
Central heating (CH) return sensor overheating
What causes this fault?
This fault occurs when the internal sensors detect that the water flowing back from your radiators is at a dangerously high temperature, suggesting the heat isn't being dissipated correctly. The most common reasons are a blockage in the system, a failing pump that isn't circulating water fast enough, or a faulty sensor sending incorrect readings to the boiler.
This issue often comes to light during the first cold spell of autumn when the heating is turned on for the first time after summer, often due to a pump that has seized while sitting idle.
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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