I have an old spare valve which does not have any valve correction factor enclosed. Can I still use it?
Yes, old spare valves do not have this correction factor and the default value 0 is correct. If an old valve replaces the newer version, the correction factor needs to be set to value 0.
Do I need to recalibrate the instrument when a dispensing valve is changed?
No, you do not have to recalibrate the instrument, because the valve performance is so consistent. However you must apply the valve correction factor to the instrument through the FillIt software.
What is the orifice diameter (OD) of the dispensing valve?