Low
d.08 on Heatline Compact 24

Your boiler is simply reporting that it is currently receiving a signal from your wall thermostat to turn on the heating.

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

Current state of the 230V room thermostat

From this model's manual
Verified against the Heatline Capriz Plus installation & service manual, page 25.
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 your wall thermostat to see if it is calling for heatTurn the temperature dial on your wall thermostat down to see if the code disappearsIf the code persists when the thermostat is off, check the wiring connections at the thermostat

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