BoilerFaultCodesYour boiler has detected that the water inside it is getting too hot, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: ALTERNATING 'H' 'E' GO TO FRAME 86
What causes this fault?
This fault occurs when the water within the boiler exceeds a safe temperature limit, triggering a safety shut-off to protect the internal components. It is physically caused by a lack of water flow, often due to a broken internal pump or a blockage in the pipework that prevents heat from being carried away. In some cases, a faulty sensor may be incorrectly reporting that the system is overheating when it is actually at a normal temperature.
This issue often surfaces during the first few cold days of autumn when the central heating is turned back on after being idle all summer, which can cause the pump to become stuck.
DIY fix possible
Check that all radiator valves are fully openEnsure the boiler pressure is between 1 and 1.5 bar on the gaugeWait for the unit to cool down and press the reset button
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like HE — no call-out fees, no surprises.
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Ideal Esprit HE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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