I have an adjustable propane regulator that I plan to have up to 10 PSI maximum. It's got a POL fitting, and works fine on a regular barbecue tank. However, rather than connect to the tank directly, I want to have a dedicated pipe coming through the wall for propane with the tank outside. I have a 20 PSI regulator attached to the tank on the outside for the purpose, so it looks like:
tank -> 20PSI regulator (with 3/8" hose) -> 3/8" to 1/2" adapter -> 1/2" pipe -> 1/2" ball valve -> (my regulator goes here)
What I'm unsure about is what fitting I can use to go from POL to the ball valve. My basic understanding says something like this: https://propanewarehouse.com/shop/fittings/pol-fittings/female-pol-x-14-mnpt/
I'm concerned about the pressure though. My understanding is that POL valves are meant to take the high-pressure gas from the tank. But rather than high-pressure gas, I've got a max of 20 PSI coming in (probably less because we're going from 3/8 -> 1/2 on the input). So I have two questions: 1) Is this the correct fitting? 2) Is the pressure here okay? Is it valid to go from a 1/2" pipe at relatively low pressure (compared to tank pressure) to POL? Will it cause me to lose appreciable pressure?
Assuming I can't do this, what's my next option? Remove the POL fitting from the regulator and use something else?