New pool build low flow rate

[Davegnh]

Been helping a friend getting his new pool up and running.
Setup
Sand filter, pump STA-RITE SuperMax VS 1.5hp, heater aguacomfort act1100 heat pump 93kbtu, equipment 60 ft from pool, 1.5" flex PVC pipe 1 run for returns and 1 run for drain/skimmer, frog system (I know pool builder said swg would ruin his steel supports), steel vinyl pool half in ground 11k gallons.

He has to run pump at 2800/2900 RPM (3k max cont) to keep the heater going which needs 20 gpm min to run. I had him try bypassing filter no change. It seems like should not be at 90% max of a vs pump for normal operation before any increase in pressure due to filter build up wear and tear.

Does this seem right/normal? Looking at pump for this flow it's a 45-50 ft head for 20 gpm. My pool runs at 1000 RPM for same flow rate but better plumbing and uses 1/10th the power. I'm thinking his pb screwed up something. Very least seems like needs much larger pump but wondering if something else is wrong.

Thanks for input.

Dave

 

[ajw22]

Flex PVC is a red flag. Could be he has a kink in the flex PVC requiring the high RPM to get adequate flow.

I always try and discourage the use of flex PVC. Underground PVC problems are almost always with flex PVC.

 

[Davegnh]

No kinks seen before pipes were buried. Is this easier to crush when covering with soil?

 

[ajw22]

Is this easier to crush when covering with soil?

Sure is.

 

[gdmacfarlane]

In the entire history of the internet, this may be the first time "asking for a friend" is legit. I can verify he is here- I am the friend.

If the flex PVC has become kinked during or post burial - any advice on how to proceed? Is there a way to test the hypothesis? What is the remedy? Will we need to unearth the plumbing? Also - should this be my responsibility? Or the pool builder.

Also - is there a possibility that the 60' length is just too far of a run for 1.5" pvc? Should the builder have used 2"?

 

[Davegnh]

Crud I've been found out... Definitely for a friend.

 

[ajw22]

In the entire history of the internet, this may be the first time "asking for a friend" is legit. I can verify he is here- I am the friend.

Welcome to TFP.

If the flex PVC has become kinked during or post burial - any advice on how to proceed? Is there a way to test the hypothesis? What is the remedy?

Read this long thread. @Casey is a TFP Expert and unfortunately did not heed the advice to not use flex PVC on her new build and within a few months it got clogged. As you will read she eventually dug along her deck and repiped the line with solid PVC.

Imagine Illusion 40 Complete 10/19/21

Why can't you run the pipes the other way to the skimmer and just go around the deck passed the slide.

www.troublefreepool.com

Will we need to unearth the plumbing?

Depends if you can easily locate it and you know where to dig. Sometimes the pipe is buried under a concrete collar or deck.

Also - should this be my responsibility? Or the pool builder.

That is between you and your builder.

In my opinion using flex PVC is always beneficial to the builder in less time and effort and never beneficial to the pool owner.

Even if the problem with your flex PVC is found and fixed to me it is a ticking time bomb that will only cause problem sometime in the future.

Also - is there a possibility that the 60' length is just too far of a run for 1.5" pvc? Should the builder have used 2"?

No and probably no. 2" would have been better but 1.5" is adequate.

There is a lot you and your builder should have done differently in your build but you were not here asking for advice at that time.

 

[Davegnh]

Sounds like most likely some sort of blockage in the system. Hopefully the PB will be helpful with investigating what the issue is.

thanks,

 

[Davegnh]

Pool builder says just a clogged filter due to algae.

 

[ajw22]

I had him try bypassing filter no change.

Pool builder says just a clogged filter due to algae.

Did he bypass the filter with no change?

 

[Davegnh]

Looking back at the readings. At 2350 RPM power went from 385w with filter to 418w bypassed 8%. This didn't seem to be enough change to indicate a clogged filter. Heater could run bypassed and ran for awhile at this speed with filter after bypass test. Then had to increase pump speed to 2900 to 3000 to get heater to run again.

He has been fighting a slight haze when he opened up the pool. Very minor algae water was 50 to 60 f. I wouldn't have thought would have been enough biological material to clog up a brand new fill of sand.

Dave

 

[Casey]

Flex pipe is horrible. I told my pb I wanted rigid pvc n he showed up with that rolled coil. It will collapse sooner or later n you'll be forced to go it alone unless you want to play the waiting game on the builder n pay their astronomical fee to redo what should have been done right the first time. My pool was only operational for less then 3 months when all heck broke lose. It went down in July n he was going to make me wait til the end of the year to fix it so I did it myself.

 

[Davegnh]

Pool builder talked him out of saltwater chlorine generator do to the risk of corrosion on steel supports but then used flexible PVC which has risk of collapse/failure... Plus I just learned this material is more susceptible to termite damage which my friend had issues with on his house. Don't think I'll ever understand this business. I still think flexible PVC can be used correctly in the right application but always surprised pool builders don't give options or education they can upsell people very easily.

 

[Davegnh]

Flex pipe is horrible. I told my pb I wanted rigid pvc n he showed up with that rolled coil. It will collapse sooner or later n you'll be forced to go it alone unless you want to play the waiting game on the builder n pay their astronomical fee to redo what should have been done right the first time. My pool was only operational for less then 3 months when all heck broke lose. It went down in July n he was going to make me wait til the end of the year to fix it so I did it myself.

Curious why you allowed your pool builder to install something that was not in your contract hopefully he paid you back for all your expenses. Sorry this happened.

 

[Casey]

Curious why you allowed your pool builder to install something that was not in your contract hopefully he paid you back for all your expenses. Sorry this happened.

Down to the wire. My late husband was sick with dementia. I lost my GAF n just let them do it n hoped I wouldn't have to go in for several years to replace it. That's the honest answer.

 

[gdmacfarlane]

Here comes a moment of closure. Problem solved! There was a little piece of plastic that had broken off of the pump housing. Apparently, it was causing a tiny bit of air to get pulled into the pump. Not enough to prevent the system from working, but enough to reduce the flow significantly. I have the pump running in its mid range (2350 RPM) and the heat pump is running fine. Thank you all for your advice. Hope to see you all back for my next problem!

 

[Davegnh]

Glad you can enjoy your pool. Keep up on the chlorine and watch the PH.