High
59 on Viessmann Vitodens 300-W

Your boiler is unable to provide hot water because it has lost its connection to one of the sensors that monitors the temperature inside your hot water tank.

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: Cylinder temperature sensor 2 lead break

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.

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Related fault codes

51View →58View →A7View →

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