Vaillant F75: Pump or pressure sensor fault
May need an engineerWhat it means
The boiler cannot detect a pressure change when the pump runs. Sensor or pump.
Safe things to try first
- Check pressure is 1 to 1.5 bar. Nothing else to try safely.
When to call an engineer
Usually a pressure sensor (a small, common part) or the pump.
Never remove the boiler cover or work on gas components yourself. It is illegal unless you are Gas Safe registered, and it will void your warranty.
Fix Vaillant F75 today
Boiler repair from £75. 92% of repairs fixed on the first visit with parts from the van.