Low
1P4 on Atag iC Range

Your boiler has detected that the water pressure is getting too low and needs a top-up to prevent it from shutting down.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Pressure 0.5–0.8 bar — filling needed

Shared across the iC Range range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 blue-handled filling link underneath the boiler.Slowly pull the lever down to allow water into the system.Watch the pressure gauge and close the lever when it reaches between 1.2 and 1.5 bar.

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Related fault codes

118View →1P5View →

All 33 fault codes on the iC Range

Seeing a different code? Every code this model can display, in one place.

102040506178101102104105108109110111112114117118119129133140151154180181201203303304501612

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