BoilerFaultCodesYour boiler has shut down because the water returning from your radiators is too hot, which usually means the water isn't flowing through your system correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Maximum return temperature exceeded – check circulation
What causes this fault?
This fault occurs when the water coming back into the boiler is too hot, which prevents the system from cooling down the internal components. The most common reason is a lack of circulation, often caused by a failing pump, a blockage in the pipework, or too many radiator valves being closed at once.
This issue often surfaces during the first cold spell of autumn when heating systems are turned back on after sitting idle for months, which can cause internal pumps to seize.
DIY fix possible
Check that at least two or three radiators have their valves turned fully to the open positionEnsure all radiator valves (TRVs) are not stuck in the closed positionReset the boiler using the 'Reset' button on the control panel
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A boiler cover plan would cover faults like E19 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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