Tapping well line, worried about pressure...

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I want to add water to a detached building on my land. Trying to bring it from the existing structure would be near impossible. So I want to tap into the black poly line from the well to the house.
My concern is that because of the elevation difference between the house and the detached building, I am thinking that the pressure in the detached building will be lower than the house because of the head pressure on the line to the house.
What do you think?
I am worried that as I use the water in the detached building the pressure in the house will not equalize with the water in the house. I'm worried that the result will be running out of pressure in the detached building and the pressure switch in the house does not turn on the well pump.
welltap.jpg
 
I admit I know very little about tapping well lines, but I see a big problem with losing water pressure in your home if something was to go wrong in the detached building. With this being said, I will remain silent until some of the well experts chime in.
 
I am guessing that a check valve is located near the pressure tank. If you tap in before the valve, there is a strong chance that you will lose the prime on the well. (unless there is a foot valve at the end of the well's suction line.) I also doubt you will have any pressure at the new building since the tap is before the pressure tank. Talk to a well person for correct answers. Hope it does work out for you.
 
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I have looked for a check valve at the pressure tank. Unless it is internal to the tank which I have never heard of, my assumption is the well pump has the only one.

Any idea of the issue of the water pressure?
 
If I am understanding your drawing correctly, the detached building is 30 feet higher than the house. Every 1' of heighth of water equals .434 PSI of pressure. So, you should have ~ 13 PSI less pressure in the detached building than in your house. So, unless your pressure switch is set extremely low, you should get water at the building at all times, though not at as high a pressure as in your home.
 
If I am understanding your drawing correctly, the detached building is 30 feet higher than the house. Every 1' of heighth of water equals .434 PSI of pressure. So, you should have ~ 13 PSI less pressure in the detached building than in your house. So, unless your pressure switch is set extremely low, you should get water at the building at all times, though not at as high a pressure as in your home.

Sorry if the drawing is confusing... but yes 30 ft elevation above the house. 13 PSI doesn't seem to bad. I don't know at what psi my switch calls the pump.... what is typical?
 
The well line is black poly. Im figuring on a barbed tee with crimp rings. Is this the most reliable connection type?
 
Barb fittings are fine, but use stainless, galvanized or brass. Two hose clamps, quality counts here too.

You need no tank in the detached building, no check valves anywhere but in the well and like Phisfood said, there will only be 13 lbs difference. You could crank up the switch to solve that problem.

If you have a submersible pump, there should be no shortage of pressure when two people are using water as long as it's not more than the pump can keep up with.
 
Barb fittings are fine, but use stainless, galvanized or brass. Two hose clamps, quality counts here too.

You need no tank in the detached building, no check valves anywhere but in the well and like Phisfood said, there will only be 13 lbs difference. You could crank up the switch to solve that problem.

If you have a submersible pump, there should be no shortage of pressure when two people are using water as long as it's not more than the pump can keep up with.

I thought about raising the press a little but I'm terrified afraid of the polybutylene pipe in my house. I have read all the stories and law suits about the stuff. I was young and dumb when I bought the house and didn't know the time bomb I had. No leaks yet but the thought of raising the pressure seems like tempting fate.

No need for the tank? That's helpful. I was a little worried being so close to the well pump I might have surges at the detached building when the pump runs.

Thanks for the help!
 
Am I missing something here????

Your drawing indicates that the line you are going to tap into is the line between the foot valve and the inlet of the pressure pump which appears to be in the main dwelling.?

Or , is there another delivery pump at the well site ??

Ive worked alot with pressure systems from wells here in the Australian Bush. If you are proposing to have a double line coming from the foot valve IE suction line, It wont work. You get a pressure differention between the lines.
hence , suction on the main pump is compromised.

Please fill me in a little more on this.


DC
 
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Am I missing something here????

Your drawing indicates that the line you are going to tap into is the line between the foot valve and the inlet of the pressure pump which appears to be in the main dwelling.?

Or , is there another delivery pump at the well site ??

Ive worked alot with pressure systems from wells here in the Australian Bush. If you are proposing to have a double line coming from the foot valve IE suction line, It wont work. You get a pressure differention between the lines.
hence , suction on the main pump is compromised.

Please fill me in a little more on this.


DC


There is no other delivery pump, Why would the pump be compromised?
I have seen several systems of the same make up that have a spicket right at the well pump tapped off of that line. Beside the elevation concern I have what is the difference?
 
You will need to increase the size of the suction line from the junction up ONE size only .
also , a non return valve on the separate building inlet ON / OFF tap.
If there is a less than totally sealed valve in the building , it will return air into the main suction line and delivery will be lost.

In a sealed system it works very well , however this proposal is interupting the main suction line from the well , with manually openable valves,(unless you plan to not use any water in the separatte building via taps)

The elevation is not really a problem,

why dont you run another delivery line from the main house to the separate building , it would maintain the same delivery pressure and not have potential for air compromise.

DC
 
You will need to increase the size of the suction line from the junction up ONE size only .
also , a non return valve on the separate building inlet ON / OFF tap.
If there is a less than totally sealed valve in the building , it will return air into the main suction line and delivery will be lost.

In a sealed system it works very well , however this proposal is interupting the main suction line from the well , with manually openable valves,(unless you plan to not use any water in the separatte building via taps)

The elevation is not really a problem,

why dont you run another delivery line from the main house to the separate building , it would maintain the same delivery pressure and not have potential for air compromise.

DC
I want to add water to a detached building on my land. Trying to bring it from the existing structure would be near impossible.

Air in the line at the detached building is an good point I think. I'm not completely sure though. It seems like the pressure tank at the house would keep pressure on the line at the detached building to keep air out.
 
It seems to me there is a little confusion. Is your well pump in the house, or is it a submersible pump in the well?
 
Am I missing something here????

Your drawing indicates that the line you are going to tap into is the line between the foot valve and the inlet of the pressure pump which appears to be in the main dwelling.?

Or , is there another delivery pump at the well site ??

Ive worked alot with pressure systems from wells here in the Australian Bush. If you are proposing to have a double line coming from the foot valve IE suction line, It wont work. You get a pressure differention between the lines.
hence , suction on the main pump is compromised.

Please fill me in a little more on this.


DC

There seems to be some confusion here. I have a submersible pump in the well. I assume it has to have a foot valve on it. there is no check valve anywhere else in the system. The is no pressure pump at the main dwelling just a tank and switch.
 
Yup, there is some confusion. It's not a jet or a centrifugal, it's a submersible. So no suction anywhere. All pipes are under pressure from the top of the pump to the furthest faucet. No air to worry about, no more check valves needed than the one built into the pump and no more tanks required. He is simply adding another fixture to a pressure line. Where he comes off for that fixture doesn't matter. The only concern is the 30 feet of difference in elevation which is going to cost 13 pounds.
 
Thanks,

It happens, it wouldn't be the first time I misread a post and went on and on about something that meant absolutely nothing.:confused:
 
Well I thank everyone for the great comments! I always enjoy learning a little more about the trades. You guys are definitely a great plumbing source. I feel more informed for this up coming project! Thanks.
 

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