Medium
F72 on Glow-worm Ultracom 2 SXI

Your boiler has detected an inconsistent temperature reading between the water leaving the boiler and the water returning to it.

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

Permanent temperature difference between flow and return heating sensors

Shared across the Ultracom 2 SXI 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F70View →F71View →F73View →F75View →

All 75 fault codes on the Ultracom 2 SXI

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

ErrF00F01F1F10F11F20F22F23F24F26F27F28F29F32F49F61F62F63F64F65F67F68F70F71F73F74F76F77F83F84F85F86P.01P.02P.03P.05P.06P.07S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.53S.54S.96S.98

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