Low
S.02 on Heatline Monza

Your boiler is currently checking the water circulation pump before it fires up, which is a standard part of its startup 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.

Technical description

Pre-run pump

DIY fix possible

No action required; this is a normal status messageWait for the boiler to complete its startup sequenceMonitor the display to see if it progresses to a heating or hot water mode

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Related fault codes

S.03View →S.06View →

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