To CSV or not to CSV.

[Larry Schwarcz]

.....
1 GPM was derived from being about 5 times more than really needed to keep the pump/motor cool, as they are cooled by the water that passes over the motor and through the pump.
......

Maybe I'm missing something here. If the key difference between a CSV and a PRV is your patented gap to keep a small amount of water flowing to keep the pump cool then is there really an advantage of a CSV over a PRV when using a submersible pump? If the pump is always 100 submersed in water wouldn't a PRV work as well if also set to 50 PSI to keep the pump cool?

Thanks again for all of your help!
Larry.

 

[Reach4]

Maybe I'm missing something here. If the key difference between a CSV and a PRV is your patented gap to keep a small amount of water flowing to keep the pump cool then is there really an advantage of a CSV over a PRV when using a submersible pump? If the pump is always 100 submersed in water wouldn't a PRV work as well if also set to 50 PSI to keep the pump cool?

Thanks again for all of your help!
Larry.

No, you need water flow to cool the motor. You could use a PRV with an external bypass to pass a limited flow of water.

An external bypass could clog if there is big-enough sediment. The CSV starts open, so it would self-clear a potential clog.

Suppose a 40/60 pressure switch-- if you used a 50 psi PRV, once the pressure rose to 50, there would be no flow. The pressure would not rise to 60 to shut off the pump. No flow would cool the pump, although a 1/2 HP motor may survive with no flow. Flow is better for sure.

 

[Sponsor]

 

[Larry Schwarcz]

No, you need water flow to cool the motor. You could use a PRV with an external bypass to pass a limited flow of water.

Suppose a 40/60 pressure switch-- if you used a 50 psi PRV, once the pressure rose to 50, there would be no flow. The pressure would not rise to 60 to shut off the pump. No flow would cool the pump, although a 1/2 HP motor may survive with no flow. Flow is better for sure.

And just to confirm, if I'm not running any water, the CSV will still allow that 1 GPM through so the PSI after the valve will increase to 60 PSI so the pump will shut off? I'm thinking it would be bad to have the pump running all the time .

Thanks again!
Larry.

 

[Bannerman]

I'm thinking it would be bad to have the pump running all the time

Correct!

not running any water, the CSV will still allow that 1 GPM through so the PSI after the valve will increase to 60 PSI

Correct!

If your pressure switch is configured for a 40/60 psi pressure range, and if the CSV is configured to supply 50 psi constant while the pump is operating, the pressure tank will continue to be pressurized to 50 psi. The 1 gpm passing through the CSV once there is no further water required, will cause the pressure tank to become filled with an additional 10psi to cause the pressure switch to shut off the pump @ 60 psi.

 

[Chucky_ott]

I'm thinking it would be bad to have the pump running all the time .

I know what you meant and I know what Bannerman meant but to clarify, a pump that runs all the time while actually pumping water is good. A pump running all the time while not pumping water (deadhead), is bad.

And the CSV, since it will prevent cycling, is essentially letting the pump run for as long as there is a (sufficient) call for water.

 

[Larry Schwarcz]

UPDATE:

UGH! After all of this mess trying to see if there's a pump in my price range has been getting in the way of me actually buying a pump!

I've heard enough good things about the Hallmark and just ordered one and a check valve from Amazon. They're supposed to be delivered on Sunday so hopefully I'll have a working well again by Monday.

It's going to be a hot weekend here in the Portland, OR area and I don't want our plants to die!

Thanks again for all of the great help and information from everyone here! Once I get it installed and working I'll post updates. Hopefully this one won't die in just a few days.

Thanks!
Larry.

 

[Valveman]

UPDATE:

UGH! After all of this mess trying to see if there's a pump in my price range has been getting in the way of me actually buying a pump!

I've heard enough good things about the Hallmark and just ordered one and a check valve from Amazon. They're supposed to be delivered on Sunday so hopefully I'll have a working well again by Monday.

It's going to be a hot weekend here in the Portland, OR area and I don't want our plants to die!

Thanks again for all of the great help and information from everyone here! Once I get it installed and working I'll post updates. Hopefully this one won't die in just a few days.

Thanks!
Larry.

Hallmarks seem to be holding up fairly well as long as you get the Stainless one and not the Cast Iron version.