I have a small dilemma, and I would like to solve it before I do a bunch of landscaping on my property.
The house is fed from a drilled well, about 50 feet away from the foundation. There is a single 1-1/4″ black plastic line that goes under the footing, under and across the basement floor, and up through the slab to the mechanical room.
I would like to feed my shop from the well, and need to know if I can tie into the water line next to the well (which wouldn’t be a problem as far as ease and location) or should I run a new 1″ line from the pressure tank to the shop (which will be a pain because the shop is 140′ +/- from the mechanical room and on the other side of the house, and I have ledge problems.
I *think* I need to run a line from the pressure tank, on the demand side, but I don’t know WHY. If I put a separate pressure tank in the shop, what is there to prevent both tanks from being fed when only one might be demanding water?
FWIW, I can understand the principles of it once somebody explains them to me. Any plumbers or water gurus in the house? This is silly, I should know this stuff, but the only system I have ever seen with two primary demand locations had a separate feed line after the pressure tank.
Replies
Well at 100' an 11/4" line can handle 70 fixture units at 40 to 60 psi.
quick guide to f.u. bath tub =4 toilet = 2.5 lav =1 kit sink = 1.5
I see no need to run a new line from pressure tank.
You only need to add a pressure tank in your shop if there is a check valve between the existing pressure tank & where you tie into it assuming your tank is big enough for what you are doing.
Adding a pressure tank at your shop with check valve will keep the systems separate only as far one back feeding the other.
don't want to get to technical hope this helps
I'd prefer you get as technical as you want to be, or can be. In other words, what's the best way to do this, and how?
Well lets see if this works look at attached drawing.
there should be a check valve on your system. Either at point A , B or C
Point A --run a line from pump or tee in line like shown your existing tank will run both house & shop --not knowing the size of you tank I'll assume it can handle the minimal plumbing your installing in your shop.
Point C--- same answer as point A
point B if that's the configuration then you need another pressure tank in your shop or your pump will run anytime you use water in your shop. Also you need to put in another check valve before the tank in shop to isolate the tanks from each other so there not trying to equalize with one another.
Multiple tanks on a single pump is not common but I have done it when one tank was not large enough for the system.
Plumbbill, any chance you can email me the attachment you posted? I'd like to print it and keep it in my files for my records assuming you wouldn't mind. I plan to print out your detailed explanation to accompany it. I'm sure SOME day I'll run into this question/issue myself with a HO.
Thanks.If at first you don't succeed, try using a hammer next time...everything needs some extra persuasion from time to time. -ME
Bill,
Thanks very much, it makes a lot more sense to me now. Basically if the check valve is either between the well pump and the tee to the shop, or after the pressure tank, it won't be a problem. Only thing I worry about is, if the check valve is at point A, it is going to be a problem backfeeding the well pump? I assume the well pump has a check valve of its' own.
Dumb question, it has to, otherwise the pump would fill up the pressure tank and then backfeed immediately back to the well.
Not all of this system is installed. I have the well pump in and the supply line and electrical coming up through the basement slab so far, no pressure tank or valves yet. So I can configure the system any way I want to. The shop will have a hose bib, a utility sink and possibly a toilet.
Yup --your right on most "new " pumps have integral checks in them but not 100% of the time.
Hose bibb mop sink & toilet total about 10 fixture units a 1" line at 40 to 60 psi can handle 39 f u's @ 100'.
Point C is the ideal & preffered location of check valve.
& one last thing I had to add the point A reference in their cause I saw that once. I think someone wasn't using common sense when the built the system. It happens
Good luck
Not silly. Thanks for asking. That's how we learn, in this case me (and others) from your question.
Certainly no expert here, all I have is one hydrant teeing off before my pressure tank. Never been a problem. The second tank is interesting. Both tanks will be fed when pressure dictates. Assuming similar elevation, no problem.
PAHS Designer/Builder- Bury it!
I wouldn't install a separate pressure tank in your shop. I installed a large system with a pressure tank near the pump and one several hundred yards away. The two tanks fought one another. The nearer tank would reach pressure and the pump would shut off. Then it would equalize with the second tank, draining down. That would kick the pump on again. It would pump on quickly then stop. Then drain down, then start again. This would keep on until both tanks finally got full.
Your system would be much smaller and closer together, so may not have any problem at all, but I don't see how you'd need it so long as the check valve were in the pump and not at the existing pressure tank.