Pump will build pressure and drop pressure

Truittknicely

Member
Jul 12, 2019
10
Midlothian, VA
I am having an issue with my Jandy pro flo pump. The system is new and has only been in place since May and up until a couple of days ago worked fine.
I have a salt water pool and sand filter. I’m the company that did the install has left me high and dry and provided no instruction or support.
A little background- until this week my in ground pool did not have cement so as you can imagine lots of dirt/clay was getting into the pool from everyday use.
I had no instructions and I consistently vacuumed the dirt from the bottom using an in-line vacuum and always vacuumed on “filter” mode which I now realize was a mistake. To make things worse I didn’t know I should be backwashing regularly and this all seemed to come to a head on Wednesday when my returns were dispersing dirt back into the pool. I also noticed at that time that my flow was intermittent.
I proceeded to backwash rather heavily to try to rectify the problem and even while backwashing the flow was intermittent.
I also had dirt and tiny pieces of gravel that had gotten inside the pump.
I was able to suck all of that out with a. Shop Vac and even went so far as to take the pump apart and cleaned some grit from around the impellar and confirmed it was not clogged or broken.
I put everything back together and ran the pump on recirculate to see if the filter was the issue but I get the same result.

The main symptom is that the pump primes and I can see the water rise into the pump and just before it gets to full pressure you can hear the pressure release and then the water flow drops almost to nothing and stats over again. The gage shows it only gets to about 8 and then drops to 0 and this is continuous.

Thinking I had a seal issue I replaced the oring on the pump lid, used ample lube and the problem still happened.

Any other suggestions on what could be causing this issue? I assume it’s a leak but could it be a clog?

We are very disheartened because our pool is brand new and we can’t even use it now that we finally have cement!
 
Welcome to the forum!
What you are describing is most likely a suction side leak. You worked on the pump lid, good job on that. What about the drain plugs? Check those.
Can you post a picture of your equipment pad? Make one picture focused on the suction side plumbing.
Can you fill out your signature? Really helps us help you.
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.
 
Welcome to the forum:wave:

Are you sucking in air at the skimmer (pump running)?
No, the water level is sufficient and no air is getting in through the skimmer.
Welcome to the forum!
What you are describing is most likely a suction side leak. You worked on the pump lid, good job on that. What about the drain plugs? Check those.
Can you post a picture of your equipment pad? Make one picture focused on the suction side plumbing.
Can you fill out your signature? Really helps us help you.
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.
 
The drain plugs? Do you mean the ones on the pump? The seem to be tight - no water is leaking.
Yes. They might not leak water. But can pull in air. Not likely the issue, but something to check.
The lines are very clean looking -- did they paint them after gluing them?
 

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Yes. They might not leak water. But can pull in air. Not likely the issue, but something to check.
The lines are very clean looking -- did they paint them after gluing them?
I just tried the “garden hose” I saw on you tube at each connection and the drain plugs and the lid and no change.
Is there anything else we can check?
I have someone coming on. Sunday but we. Would really like to swim this weekend
 
OK -- one more try. At the skimmer, remove the basket. Do you have a main drain? Be sure to pick the hole in the bottom of the skimmer that goes to the pump. Put a hose in there. Full force. Start the pump. See if forcing water to the pump helps.
 

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