High
F85 on Heatline Solaris

Your boiler's temperature sensors are reporting conflicting information because they are detecting heat from the same spot, causing the system to stop heating for safety.

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

Flow and return heating sensors fault: Flow and return heating temperature sensor connected to same tube

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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