BoilerFaultCodesYour boiler has shut down because the water returning to the unit is too hot, typically meaning the heat isn't being distributed around your home properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Maximum temperature - Return temperature T2 too high
What causes this fault?
This fault occurs when the water traveling back into the boiler is nearly as hot as the water leaving it, indicating that heat isn't being transferred to your radiators. The most common reasons are a failed pump that isn't circulating the water or a blockage in the system, such as a build-up of sludge or closed radiator valves.
This fault often appears when heating is first turned on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Ensure all radiator valves (TRVs) are fully open to allow water to circulate.Check that your external heating pump is running if you have a separate system pump.Reset the boiler by following the instructions on the control panel.
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A boiler cover plan would cover faults like 919 — no call-out fees, no surprises.
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Ideal Response SE is discontinued — time for a new one?
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