BoilerFaultCodesViessmann 58 Fault Code
The Viessmann 58 fault code means: your boiler is unable to heat your hot water because a sensor responsible for monitoring the cylinder temperature has lost its connection or stopped working.. It appears on 9 Viessmann models in our database.
Technical description: No DHW heating - Cylinder temperature sensor/comfort sensor/loading sensor lead break
What causes the Viessmann 58 fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors your hot water tank. The most common reason is a physical breakage in the sensor’s wiring or internal electrical failure within the sensor itself, which prevents the boiler from knowing how hot the water is. For safety reasons, the boiler stops heating the water entirely because it can no longer prevent it from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Viessmann models that show the 58 fault code
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Source
Viessmann 58 fault code information on this page is sourced and cross-checked against the official Viessmann service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026