Medium
F.13 on Vaillant ecoTEC plus System

Your boiler has lost the connection to the temperature sensor in your hot water tank, meaning it currently doesn't know when the water has finished heating up.

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.

Technical description

Short circuit: Domestic hot water cylinder temperature sensor. Possible cause: NTC sensor defective, short circuit in the cable harness, cable/casing

Engineer required

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

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