Low
7 on Atmos Intersystem HE40 C

Your boiler has detected that the temperature inside the unit is dropping close to freezing and has temporarily activated its built-in frost protection to stop the water inside from turning to ice.

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

Appliance frost protection intervenes (heating heat exchanger)

From this model's manual
Verified against the Atmos/Atmos Intersystem He26 installation & service manual.
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

Check that your heating is not accidentally switched off completely.Ensure your property's room thermostat is set high enough to call for heat.Verify that the boiler's external condensate pipe is not blocked or frozen outside.

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Related fault codes

6View →8View →

All 11 fault codes on the Intersystem HE40 C

Seeing a different code? Every code this model can display, in one place.

012456810, 11, 12, 13, 1420, 21, 22, 23, 2429, 30

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