Lots of well problems

[rypkr937]

What pressure is 3/4 pex rated for?

https://www.pexuniverse.com/pex-tubing-technical-specs

200°F at 80 psi
180°F at 100 psi
74°F at 160 psi

So 160 psi given it's going to be pretty close to ambient?

 

[rypkr937]

Is the pressure before the pressure tank greater than the pressure after the tank? If I have 3/4 PEX plumbing further down the line in my house already I don't see why using it between the top of my drop pipe and the pressure tank would be an issue unless there is greater pressure there?

If I have XYZ pressure at my shower head, isn't that the same XYZ pressure all the way back at my well drop pipe since it's all connected?

 

[Sponsor]

 

[LLigetfa]

My guess is Cary is contemplating holdback pressure from a CSV.

 

[Valveman]

My guess is Cary is contemplating holdback pressure from a CSV.

Yes the 160 PSI is a good rating for cold water. Pressure before the CSV can be 100-150 PSI depending on the pump.

You already have some 3/4 pex. The longer the distance of 3/4 pipe the more restriction there is and the lower the pressure will be. It is usually best to give pressure and flow to the pressure tank without any restriction, like with larger pipe. Then after the pressure tank the lines get smaller an pressure is lost. At 5 GPM flow you can lose 3 PSI for every 100' of 3/4 pipe. So if you have 300', you will lose almost 10 PSI.