I'm getting ready to build a small summer home. I want the well water pressure tank to be underground, in part because of possible freezing. I've already bought the tank (fiberglass) and 4' of 36" pipe for the vault. Question is: How much plumbing must be in the vault?

I assume that I can put the pressure switch in the cabin (about 30' from the tank). Same with the pressure gauge. That leaves just the pressure relief valve, backflow preventer, and a drain valve in the vault, right?

The pressure tank I bought allows the bladder to be serviced from the top. No need to pull the tank for this operation. But if the tank does need to be pulled, are there some kind of disconnect flanges to help with this? Maybe something like the flanges on circulating pumps? I don't want to end up having to do complex plumbing in a vault that has limited space.

Mark