What does the Viessmann Vitodens 100-W F32 fault code mean?
The F32 fault code on the Viessmann Vitodens 100-W indicates a problem with the expansion vessel, which is responsible for maintaining the pressure in the heating system. A faulty expansion vessel can lead to pressure fluctuations and may cause the boiler to shut down to prevent damage.
Common Causes
- Loss of Pre-charge Pressure: The air pressure inside the expansion vessel may have dropped, affecting its ability to absorb pressure changes.
- Physical Damage: The expansion vessel may be damaged or corroded, leading to leaks and loss of functionality.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as working with the boiler’s pressure system can be dangerous. Attempting to fix it without proper training may lead to further complications.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing a faulty expansion vessel on a Viessmann Vitodens 100-W is around £200 to £300. This includes the cost of the part and labour, as the expansion vessel is a critical component that requires professional handling.