What does the Vaillant ecoTEC plus F36 fault code mean?
The F36 fault code on the Vaillant ecoTEC plus indicates a malfunction with the thermostat, which is responsible for regulating the boiler’s temperature. This issue can prevent the boiler from operating efficiently or cause it to shut down entirely.
Common Causes
- Faulty Thermostat Sensor: The sensor may be damaged or malfunctioning, leading to incorrect temperature readings.
- Wiring Issues: Damaged or loose wiring connections can disrupt communication between the thermostat and the boiler.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it involves gas and electrical components that require professional expertise to ensure safety and compliance with regulations.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for the F36 fault code is around £150 to £250, which includes the replacement of the thermostat and any necessary wiring repairs. This cost reflects the complexity of the repair and the need for a qualified technician.