Medium
59 on Viessmann Vitodens 100-W WB1A

Your boiler is having trouble communicating with the sensors that measure the temperature of your hot water, which may cause your hot water to stop working or behave unexpectedly.

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

Cylinder temperature sensor 2/outlet sensor lead break

From this model's manual
Verified against the Viessmann Vitodens 100 W Wb1a installation & service manual.
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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