Medium
FILL on Atag Q 30CR

Your boiler has lost water pressure and needs to be topped up to work at full capacity again.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Water pressure is to low (<0,7 bar), flashing FILL will alternate with indication of water pressure, boiler power of 50% is possible. The installation needs to be topped up.

From this model's manual
Verified against the Atag Q 30cr 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

Locate the external filling loop, which is a silver braided hose near the boilerOpen the small valve or tap on the loop to let water into the systemWatch the pressure gauge on the boiler screen until it reaches 1.5 barClose the valve tightly and check for leaks

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