Low
i9 on Worcester Bosch Greenstar Heatslave II

The display is simply showing the current temperature of the water inside the boiler rather than indicating a fault.

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.

Technical description

Flow temperature - This is the actual temperature from the main heat exchanger displayed in real time (rounded to 0.5°C units).

Engineer required

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

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