plumbing a new well

I just had a new well drilled 280' making approx 20 gpm. I'm planning on setting a 1hp, 10gpm pump at 250'. Is this enough pump and should I use the 160 psi polypipe or schedule 80? I,m getting mixed signals from all the well guys around here. We have a 3 bed, 2 bath home and keep fresh water to about 5 horses.

The well is approximately 80 ft from the house, 100 ft from the barn and the static water level is 75 ft.

Sounds good to me and I'd use 160 unless it had to go more than 3' deep or over rocks. Then I'd go to 200 psi PE.

Gary Slusser said:

Sounds good to me and I'd use 160 unless it had to go more than 3' deep or over rocks. Then I'd go to 200 psi PE.

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I concurr, but I'm wondering what you mean by mixed signals ?

What I mean by mixed signals is:

Some are saying 1.5 hp pump and 200 psi pipe, others are saying a 1hp and 160 psi is plenty. Also, how big of a pressure tank would you go with?

The builders have stubbed 3/4 in pex out under the footing for me to tie into. Presure tank will be in the garage.

What is the peak demand gpm of the house? What is the static water level of the well? What is the TDH (total dynamic head) of the system? Those are the things you need to know to size a pump. The 1 hp 20 gpm is quite large for most houses unless you are at high elevation.

If you mean the 3/4" PEX is going to be used between the PE from the well pump and the pressure tank, have them tear it out and replace it with whatever ID PE you are using from the pump.

If you are lifting water from 200', a 1 HP, 10 GPM will give you 10 GPM at 50 PSI. A 1.5 HP, 10 GPM pump will try to pump 14 gallons at that depth and pressure. A 45 gallon size tank would be absolute minimum and an 80 gallon tank would be better. If used with a CSV1Z, a 20 gallon tank is plenty large enough and an even smaller tank is possible. The CSV will also help reduce upthrust on the 10 GPM, 1.5 HP pump, and let you use water anyway you want with constant pressure. However, the 1.5 HP could build 240 PSI on the drop pipe, so I would use Sch 80 PVC, which I like better anyway.

Or better yet, use a 15 GPM, 1.5 HP. It will be less expensive and only build 180 PSI back pressure with the CSV.

As far as the pressure tank goes, get the biggest one you can afford and that will fit the space. Small tanks mean less draw down time and more pump cycling. Within reason you can't oversize the pressure tank.