CSV 125 50psi failing

[ron958]

CSV 125 50 psi is failing closed. Valve about 4 yrs. old and no longer allowing full volume of pump to flow through valve. Pump is 3/4 hp rated at 12 gpm approximately 30 deep in the well. In the past could easily handle 2 lawn sprinklers and any water demands in the house. Lately with 2 sprinklers  going, the max pressure capable slightly above low pressure cut in 32 psi., and if any demand for water is made in the house the volume of water can’t keep up, pressure falls below low cut off and system shuts down. Back pressure between the pump and valve 120 psi. Volume no longer going through valve to meet demand.
No changes made to water system since valve installed. Any thoughts to solve issue?

[Cary Austin]

It is almost impossible for the CSV125 to fail in the closed position.  It could have something inside of it blocking flow, but the valve cannot physically fail closed.  Maybe the inlet pressure gauge is pegged and reading 90 PSI more than it should.  It could be a check valve by the CSV failed in the closed position?  Post a picture so we can see the set up.  No problem sending you another CSV125 if that is needed, but really need to find the cause of problem first.

[ron958]

Thank you for the prompt reply. I will post pictures of my system later. There are no mechanical restrictions in the water system anywhere other than manifold and valves, all of which have not been changed or modified. Only two check valves, the one built into the pump and another brass 1 1/4” check valve directly above the pump as a back up. 1 1/4” PVC  line from pump to CSV valve and 1 1/4” PVC line existing.
There is a factory installed fine mesh  screen surrounding the inlet of pump which is unobstructed.
Internal openings in the CSV must be quiet large if it’s rated capable of passing full flow of 12 GPM pump?
Can the CSV be removed and back flushed? Are all the internal components stainless?
Gauge working as pressure fluctuates between 120 and 50 PSI and down to 0 if pump is shut down,  depending on how water system is used.
Pressure gauge is on main line 6” below CSV, between pump and CSV.

[Cary Austin]

The CSV125 is actually rated for up to 50 GPM, so 12 GPM is no problem.  You say the backpressure goes from 120 to 50 depending on how the water is being used.  What are you using when it gets down to 50 PSI?   120 to 50 backpressure sounds like the CSV is working.  The back pressure should also not go to zero after the pump shuts off.  Makes me think there is a check valve after the back pressure gauge somewhere, as the CSV cannot prevent reverse flow.  The pressure before the CSV should be the same as after the CSV when the pump is not running.  Still think something else, like a check valve, is blocking flow.

[ron958]

Simplest way to resolve this, raise the pump to remove the valve which is near the top of the well, replace it with a 6” PVC nipple and pump back in service.

[Cary Austin]

If the CSV is in the well there is no way to put a  pressure gauge  before the CSV.  The CSV is not the problem. Go ahead with replacing it with a nipple. Nothing will change.

[ron958]

Further to your previous reply I did what you suggested trying to find things that would obstruct flow. Finding nothing I ran trial again with the CSV 125 50 psi.in the line. Same problem, not enough flow to satisfy two sprinklers and any open faucets in the house which quickly resulted in pressure drop that shut the pump down.
My next trial was one sprinkler and one faucet which lasted longer, but low water pressure which also eventually tripped the pressure switch.
Finally totally frustrated I removed the CSV reconnected the line started the pump and let the system fill up.
Turned on two sprinklers, full capacity, pressure about 53 psi slightly below HI cut off of 57 psi. Leaving the two sprinklers running I then turned on kitchen faucet, bathroom faucet and laundry tub faucet. No problems again pressure dropped to 38 psi.not low enough to make low pressure cut in. Pressure in the well about 70 psi, which probably means the pump still has some capacity left.
The 4” submersible pump is new, rated by the manufacturer at 12 gpm. At 30 feet which is the depth the pump is at in the well.
As you’ll see the pump is in a shallow well and not a conventional setup. Point of the exercise is to show capacity of the CSV125 50 psi and the pump in the well.
I videoed the entire episode about 6 minutes long, not sure how to send it.
Your thoughts

[Cary Austin]

Must be something lodged in the CSV125. Otherwise it could not do that. We will send you a new CSV125 at no charge. Just call during regular hours.

[ron958]

Considering  CSVS 125 50 psi.,what is the difference between it and CSV 125 50 psi. I’m talking about the internal components. Can the SS model be taken apart without destroying the valve?

[Cary Austin]

The only difference between the CSV125 and the CSVS125 is the SS body.  The internals are the exact same plastic parts.  You should never need to repair either.  But you can repair the CSVS, it will just cost more than a new CSV125.  Just call for a replacement, and send in the old valve back for an inspection.  That is not a normal problem we will want to figure it out.  Most times we find nothing wrong with the old valve, and the replacement valve does exactly the same thing.  That is usually how we figure out where the real problem is. 

[ron958]

What is the maximum gpm. possible through the CSVS 125 50 psi.

[ron958]

Sorry, just read previous replies, got my answer.

[ron958]

What pump pressure before the CSV is required for the CSVS 125 50 psi to develop its maximum rated volume of 50 gpm or is the valve fully open when pump pressure ( back pressure ) is above 50 psi. In my limited experience as volume through a pump increases pressure will decrease.

[Cary Austin]

At 50 GPM flow the CSV1125 has 10 PSI friction loss.  That means it would need a pump that can do 50 GPM at 60 PSI to get 50 PSI out of the CSV125.