What does the Viessmann Vitodens 200-W F37 fault code mean?
The F37 fault code on the Viessmann Vitodens 200-W indicates a problem with the secondary heat exchanger, which is responsible for transferring heat from the boiler to the heating system. This issue can lead to reduced efficiency and heating performance.
Common Causes
- Blockage: A build-up of debris or limescale in the secondary heat exchanger can restrict water flow and heat transfer.
- Leakage: A leak in the heat exchanger can cause a drop in pressure and affect the boiler’s operation.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer for this issue, as working on gas appliances can be dangerous and requires professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for replacing the secondary heat exchanger on a Viessmann Vitodens 200-W is around £600 to £800. This includes parts and labour, reflecting the complexity of the repair and the cost of the component.