Low
d.16 on Heatline CaprizPlus 28

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

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 24V 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 room thermostat settings to see if it is currently requesting heatAdjust the thermostat temperature dial lower to see if the status code changesIf the boiler is working normally otherwise, no action is required as this is a status indicator rather than a fault

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Related fault codes

d.15View →d.17View →

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