Medium
FILL (flashing) on Atag E Range

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

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 (<1,0 bar), flashing FILL will be altered 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 Blauwe Engel 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, usually a silver braided hose with one or two valves located underneath the boiler.Slowly open the valve(s) to allow mains water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) tightly and check for any leaks around the connection points.

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