: Check if your boiler is still under its Vaillant Guarantee before paying for parts.
: They will use a multimeter to check the resistance of the flow and return NTC sensors. If a sensor is "open circuit" or "short circuit," it’s a relatively cheap and quick replacement. vaillant boiler f64 fault
: A sensor replacement might cost around £80–£120, while a new PCB can range from £250 to over £400 including labor. : Check if your boiler is still under
Here is a breakdown of what the F64 fault means, the potential causes, and the steps you need to take to get your heating back on. the potential causes