High
F72 on Heatline Solaris

Your boiler has detected an unusual temperature gap between the outgoing and incoming water, indicating the system is struggling to circulate heat correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Permanent temperature difference between fl ow and return heating sensors

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F22View →F73View →

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