Question about placement of CSV

[1984]

The PVC pipes that go down my well and hold the pump are 1-1/4", but the pipes that run underground to my house are only 1". I've considered upgrading the 1" pipes to 1-1/4", and asked someone about this, but they said it doesn't matter because "the interior of the check valves is narrower than 1-1/4 inches, so upgrading your pipes won't do anything because the check valves will be your limiting factor." Intuitively that makes sense, but I don't know if it's true.

If there's no need for upgrading all my pipes to 1-1/4", then should I put the CVS on the 1-1/4" pipes running down my well, perhaps just before the 1" x 1-1/4" adapter?

One other question: if I leave the 1" pipes in place, what's the upper limit to GPM that I can safely get from a pump?

Thank you for the help.

 

[Terry]

Here is some information about water sizing.
Larger pipes will mean less friction loss. And distance makes a difference too. My mothers place in Bellevue benefited by changing the line to the house to 1.5". She had a 5/8" water meter and the line was about 250 feet long. With her old line she couldn't get the irrigation to work. She had seven zones.

 

[Sponsor]

 

[Sarg]

I believe it's the consensus of the knowledgeable forum members that there should only be one check valve ...... and that's the one on the water pump.

 

[LLigetfa]

I believe it's the consensus of the knowledgeable forum members that there should only be one check valve ...... and that's the one on the water pump.

While factually correct, I see no mention of a second check valve.

 

[LLigetfa]

While there are limits WRT constrictions reducing GPM of flow such as the 7 GPM dole valve pictured below, changes in ID mostly just increase the velocity so it is a matter of distance as to how much friction loss there will be as Terry mentioned.

 

[VAWellDriller]

The PVC pipes that go down my well and hold the pump are 1-1/4", but the pipes that run underground to my house are only 1". I've considered upgrading the 1" pipes to 1-1/4", and asked someone about this, but they said it doesn't matter because "the interior of the check valves is narrower than 1-1/4 inches, so upgrading your pipes won't do anything because the check valves will be your limiting factor." Intuitively that makes sense, but I don't know if it's true.

If there's no need for upgrading all my pipes to 1-1/4", then should I put the CVS on the 1-1/4" pipes running down my well, perhaps just before the 1" x 1-1/4" adapter?

One other question: if I leave the 1" pipes in place, what's the upper limit to GPM that I can safely get from a pump?

Thank you for the help.

The comment about the check valve restriction is not true....a short run or one fitting of a slightly smaller size will reduce flow, but is not as significant of a very long length of undersized pipe. I don't know what flow range you are shooting for, but there are published tables for headloss at various flow rates for pipes, fittings, pitless adapters, check valves etc. You add them all up to determine what the pump needs to be able to overcome to produce your desired flow rate. You should be able to easily get 15-20 gpm through 1" sch 40 IPS pipe (assuming not a super long run <100'). Still not knowing your flow rate, I think the CSV could go in either section of pipe.

 

[1984]

You should be able to easily get 15-20 gpm through 1" sch 40 IPS pipe (assuming not a super long run <100').

Thank you for the help! I'm not sure I understand what you mean when you say "assuming not a super long run". I understand that there will be head pressure loss from friction, but if you can pump 15-20 GPM through a small section of 1" pipe, shouldn't you be able to pump the same amount of GPM through a much longer section of pipe assuming you increased the power of the pump? Just buy a pump with more horse power to overcome friction head loss, right? Or no?

 

[Sarg]

While factually correct, I see no mention of a second check valve.

From the OPs post:

"the interior of the check valves is narrower than 1-1/4 inches, so upgrading your pipes won't do anything because the check valves will be your limiting factor."

VALVES infers more than one.

 

[VAWellDriller]

Thank you for the help! I'm not sure I understand what you mean when you say "assuming not a super long run". I understand that there will be head pressure loss from friction, but if you can pump 15-20 GPM through a small section of 1" pipe, shouldn't you be able to pump the same amount of GPM through a much longer section of pipe assuming you increased the power of the pump? Just buy a pump with more horse power to overcome friction head loss, right? Or no?

That's absolutely right...you can always bump pump size to overcome it. There is a GREAT website called engineering toolbox that has all kinds of good stuff...if you google that along with pipe friction loss you will get a table that will show headloss at varying flow rates and pipe sizes..expressed per hundred feet of pipe. When I said super long run; sometimes folks post here that are running hundreds and hundreds or even thousands of feet.

 

[Fitter30]

Every type and size of pipe, fittings and devices have published pressure drop or equivalent lenght of pipe. The larger the pipe less fiction loss= less hp for pumping. Save on material now cost you electric for years.

 

[Valveman]

After removing all check valves except for the one on the pump, the CSV just needs to be installed prior to any tees and hydrants, and before the pressure tank/pressure switch. The CSV1A is dual threaded and can be connected to 1" or 1 1/4" pipe as needed.