Medium
FILL on Atag E Range

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

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 E Range Combi 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 filling loop (a silver flexi-hose) underneath the boiler or near your pipework.Open the valves on the filling loop to allow cold mains water to enter the system.Watch the pressure gauge on the boiler until the needle reaches the green zone (typically 1.2 to 1.5 bar).Close both valves tightly and remove the filling loop if required by your specific model.

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