Medium
FILL (flashing) on Atag E22c

Your boiler has lost water pressure and needs to be topped up to function correctly 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 (<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 E32c 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 connecting two pipes near your boiler.Open the valves at both ends of the hose to let water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close both valves tightly and remove the hose if it is not a permanent fixture.

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