High
51 on Viessmann Vitodens 100-W

Your boiler has stopped heating your tap water because it is getting a faulty signal from the sensor that measures the water temperature.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

No DHW heating: Drawoff temperature sensor short circuit

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer
Search the official register →

Related fault codes

50View →

Related guides you might find useful

No hot water but heating works

Almost always a stuck diverter valve on combis.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →