Low
18 on Viessmann Vitodens

Your boiler has lost the connection to the thermometer installed outside, so it is struggling to calculate how much heat your home needs based on the current weather.

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

Temperature sensor, outdoor sensor lead break

Engineer required

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

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