Low
STOP on Atag Q 25S

Your boiler is simply letting you know that you have successfully finished topping up the system pressure to the correct level.

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

Appears on the display when water pressure reaches 1.5 to 1.7 bar during filling.

From this model's manual
Verified against the Atag Q 25s installation & service manual.
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

Ensure the filling loop or external filling valve is now fully closedCheck that the display returns to normal operation once the valve is shutKeep an eye on the pressure gauge over the next few days to ensure it remains stable

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