Medium
118 on Atag iC28

Your boiler has detected that the water pressure is too low, causing it to slow down to protect the system.

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 too low (<1.0 bar). Power is reduced by 20%. The installation should be refilled.

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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 (the flexible silver hose) underneath or near the boiler.Open the one or two taps/levers on the filling loop until the pressure gauge reads between 1.2 and 1.5 bar.Fully close both taps and ensure the code has cleared.

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Related fault codes

All 18 fault codes on the iC28

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