Medium
5.ii on Chaffoteaux Celtic 2 24 Rsc

Your boiler is struggling to provide hot water because the incoming mains water supply pressure is too low for the system to detect or operate correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Hot water does not operate over temperature range - Low inlet water pressure

DIY fix possible

Check that the mains water stopcock under your kitchen sink is fully openEnsure no other taps in the house are fully open or leaking significantlyCheck if there are any current water supply maintenance works reported by your local water provider

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Related fault codes

5.iView →5.iiiView →

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