Medium
F.13 on Vaillant Home Combi

Your boiler is having trouble 'reading' the temperature of your hot water because a sensor wire is damaged or disconnected, meaning it may struggle to heat your water properly.

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.

What the manual says

Manufacturer manual

Short circuit: Domestic hot water cylinder temperatures sensor

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 35.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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