Low
S.97 on Glow-worm Ultracom 2 SXI

Your boiler is temporarily pausing to check the system's water pressure before it starts up to provide heating or hot water.

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

Water pressure sensor check is running, demand (DHW or heating) is blocked

From this model's manual
Verified against the Glow Worm Ultracom 2 Sxi installation & service manual, page 55.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This status occurs when the boiler's internal computer is verifying that there is enough water pressure and flow before it safely ignites the burner. It is often triggered if the water pressure sensor or temperature sensors are sending slightly inconsistent readings or taking too long to respond. While it is usually just a brief safety check, if it persists, it typically means a sensor is beginning to fail or there is a minor circulation issue.

DIY fix possible

Wait for up to 15 minutes to see if the code clears automaticallyCheck that the pressure gauge is between 1.0 and 1.5 barRestart the boiler using the reset button if the code remains for more than 20 minutes

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