How to reduce 46v to 24v for a solenoid valve
Input Voltage: 24V
  Current Draw: 160mA
  Power Consumption: 3.84 Watts


I think there's significant doubt as to whether the device is an AC operated valve. This is made worse by the link not being clear but, in general, if the supply voltage is stated as 24 volts AND the current specified is 160 mA then it's highly likely that the power dissipated will be exactly 3.84 watts on a DC system.

This is because voltage x current = power and 24 volts x 160 mA  = 3.84 watts.

If it were an AC solenoid then it's highly unlikely that the power dissipated will be exactly 3.84 watts.

So, running a 24 volt DC solenoid from 46 V AC is not going to survive too long. Try researching the part better and find out what the requirements really are. I think you'll find it to be a DC solenoid. You need to confirm this first before any further answer can be made to help you sort it out.

If you check out the sort of power supplies supplied by FarmBot (your linked supplier) they are 24 volt DC: -