Medium
FILL (flashing) on Atag Q 30CR

Your boiler has detected that the water pressure inside your heating system is too low and needs to be topped up to function correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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 (<1,0 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 Boiler Ata 013 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 (a flexible metal or silver hose connected between two pipes under your boiler).Open the valves on both ends of the hose slowly to allow water into the system.Watch the pressure gauge on the boiler front until the needle reaches the green zone (usually 1.5 bar), then turn both valves securely off.

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