Fluctuating / jumping temperature on Vaillant boiler / How to replace Printed Circuit Board / Motherboard step by step
This video is for GAS SAFE ENGINEERS only, always follow manufacturer instructions.
Before to start any work on gas appliance isolate the power, turn off the gas and the waters.
1. Download manual
professional.vaillant.co.uk/d...
2. Remove front cover
3. Remove PCB cover
4. Disconnect cables
5. Replace PCB
6. Reconnect cables
7. Test it
19 май 2024