What does the Vaillant ecoTEC exclusive F90 fault code mean?
The F90 fault code on a Vaillant ecoTEC exclusive boiler indicates a malfunction in the backup system, which is essential for maintaining heating and hot water supply. This issue may arise due to various underlying problems that affect the boiler’s operation.
Common Causes
- Electrical Faults: Issues with wiring or connections can disrupt the backup system’s functionality.
- Component Failure: A failure in the backup system components, such as sensors or control units, can trigger the F90 fault code.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer to diagnose and repair the F90 fault, as it involves electrical and gas components that require professional expertise for safety and compliance.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F90 fault code is around £200 to £350, depending on the specific components that need replacement or repair. This estimate includes parts and labour for a qualified technician.