Low
H E on Evo HE 12

Your boiler is displaying an 'H' and 'E' sequence to indicate its current operating status or a diagnostic mode, often triggered by a system reset or power-up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

ALTERNATING 'H' 'E' - REFER TO FRAME 66

From this model's manual
Verified against the Evo He 12 installation & service manual, page 41.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Observe the boiler for 5-10 minutes to see if it clears the cycle automaticallyCheck that your external heating controls or room thermostats are calling for heatPerform a simple reset by turning the control knob to 'Reset' and back to 'On'

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Related fault codes

HView →EView →

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