Medium
F.13 on Vaillant aquaPLUS

Your boiler's hot water storage tank sensor has developed an electrical fault, meaning the system can no longer monitor or control the temperature of your hot water.

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 tank- NTC | NTC- plug shorted to casing, NTC defective

Engineer required

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

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Related fault codes

F.10View →F.11View →

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