Also, if you want quicker carbonation with less risk of over carbonation try this:
1) with chilled keg set pressure gauge to 30psi and leave for 24 hours
2) remove gas, pull the PRV
3) set gauge to 20psi, reattach, leave for 24 hours
4) remove gas, pull PRV
5) set gauge to serving pressure and leave
I can carbonate beer quickly this way but once again the head isn’t where I want it.