well and pump question
I have a very deep well that produces about 20 gpm here in the mountains. It has supplied me with good water for 8 years or so. It is controlled by a pressure switch on the pressure tank which has about a 30 gal capacity. The well head is located some 100 feet from the house and is fed underground by 1 inch pvc water pipe. My question is can i tap into the existing line that feeds the house with a t that would be installed about mid-way between the house and a small apt/studion i am building.? This water would come right off the high pressure side of the pump and would have to give me enough water for dishes showers etc for anyone who may live here. I do not want to over tax the pump as it is very deep and would be expensive to replace? What are your thought on this matter well and pump “gurus”?? Thanks, Tom
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That's what I did when I built my shop. Original set up was one line from well to house, pressure tank at house. New setup is tee at the well with original line to house and new line to shop, same pressure tank location at house. The pressure tank is maintaining pressure everywhere in both buildings (and all the way down the well for that matter).
You might consider upsizing the pressure tank. Mine is 119 gallons. A larger tank will mean fewer pump cycles, so the pump and relay will probably last quite a bit longer.
This will work as long as there is no backflow preventer at the inlet of the house pressure tank.
And I agree that you should have a larger tank. A 20 gpm pump operating at 30/50 psi, should have a 60 gallon pressure tank (the actual drawdown is less than half the tank volume).
An alternative to up-sizing the tank would be to put an additional tank at the new building.
We often do that on the down-stream side of water softeners etc, one at the switch is critical but we did one house that had one on either side of the filtration system (huge, complex system, 3/4 GPM well yield at 400', nasty water) and another at the guest cottage 350' across the field.
Check valve on the down stream side of the water softener only. we could take the filtration system off line for an hour and the occupants wouldn't notice.