H E Low

Evo H E Fault Code

Also written as HE — same fault.

The Evo H E fault code means: 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.. It appears on 2 Evo models in our database.

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.

Technical description: ALTERNATING 'H' 'E' - REFER TO FRAME 66
Typical repair cost £0-90 (including labour)

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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Evo models that show the H E fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Evo H E fault code information on this page is sourced and cross-checked against the official Evo service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026