Low
S.20 on Heatline CaprizPlus 24a

Your boiler is currently performing a routine self-check before it starts the main ignition process.

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

Pre-run pump

From this model's manual
Verified against the Heatline Caprizplus 24a installation & service manual, page 26.
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

Wait for 30 to 60 seconds for the boiler to complete this automatic cycle.Check if the heating or hot water starts normally after the code disappears.If the code stays on for a long time, try a simple reset of the boiler.

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