Low Information
S.22 on Glow-worm Flexicom cx

Your boiler is performing a routine self-check of the internal pump before starting the burner to ensure water is circulating correctly.

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

Pump pre run

What causes this fault?

This is a normal part of the boiler's startup process and occurs when the system sends power to the internal pump to get water moving. It happens every time you ask for heating or hot water to confirm the pump is spinning correctly before the flames ignite. It is not an error, but rather a brief verification step the internal computer performs to ensure the system is safe to operate.

DIY fix possible

No action is required as this is a normal operational status message, not a fault.Wait a few moments for the boiler to complete the pre-run cycle and ignite.If the code persists for a long time without the boiler firing, try a simple reset.

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