What does the Viessmann Vitodens 100-W F58 fault code mean?
The F58 fault code on the Viessmann Vitodens 100-W indicates a malfunction in the zone valve, which is responsible for controlling the flow of hot water to different heating zones in the system. This issue can lead to inadequate heating or hot water supply in the affected areas.
Common Causes
- Faulty Zone Valve Motor: The motor that operates the zone valve may be defective, preventing it from opening or closing properly.
- Electrical Connection Issues: Loose or damaged wiring connections to the zone valve can disrupt its operation, leading to the F58 fault code.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer for this issue, as it involves gas and electrical components that require professional handling. Attempting to fix it yourself could pose safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for the F58 fault due to a faulty zone valve is approximately £250 to £350. This includes the cost of the replacement zone valve and labour charges for a qualified engineer to install it.