Why is my filtering system built like this?

[Fronzizzle]

Hello all,

I bought a house in the fall of 2016, becoming a first-time pool owner. I've since learned a lot about the care and maintenance of above ground pools, including the winterizing and opening, from this forum and now I have another question.

My pool (it is a 4' deep oval) is surrounded by a large 60' x 40' deck. The piping for the filter system comes from the pool, travels straight for a short distance, then goes back up and over one of the joists for the deck before dropping back to the previous level and finishing at the filter. I have attached a crude sketch of it. I only included one pipe on the drawing, but both pipes (which are PVC) travel the same path.

I can't figure out if there is a design reason for the pipes to go back up and over the joist? From a performance standpoint, it causes issues sometimes - we have to keep the water level high up on the skimmer because if we don't, the pipe becomes the high point of the system and we lose suction/filtering. When the return line was installed, the previous owner hand tightened it (or less) and it constantly drips. I haven't bothered with it up until now, but I plan on fixing it before opening the pool in a few weeks and I'm wondering if I should re-do all of the piping so it comes out of the skimmer and straight to the filter instead of up and over a joist?

Mike

 

[Richard320]

Pure speculation here. It could be designed that way to allow some flexing without breaking. I've seen similar doglegs built into oil pipelines around San Ardo. Second guess, he did that instead of valves to minimize water loss when servicing the filter.

 

[cfherrman]

I could only think of support from weight, which just putting them on the ground would be better

 

[Jimrahbe]

F,

Since we are guessing anyway, my guess is that the original owner wanted to be able to work on the pump or filter without having to install any valves. If you have valves on those lines to stop the water from draining back through the pump and filter than I am just full of it... again..

Jim R.

 

[duraleigh]

Continuing the guesswork, I thought, Like Rahbe and 320, that it might be a clever "trap" that would keep the pool water from flowing out of the pump when the pump lid came off......but thinking about it, I don't think it would work like that.

Since no air can enter the system from the skimmer, the water would simply flow out of the pump basket regardless.()until the skimmer was uncovered allowing air into the pipe)......is that right???? I think so.

Using it as weight bearing makes sense until you think that a couple of pipe straps would have been far better and easier.

 

[Teald024]

I'm going with the air trap theory. But a poor one at that. The pool would still drain until the skimmer was empty, with or without the loop.

You need to keep the water level high enough to prevent air into the skimmer suction. If air can't get it, it wouldn't matter. The air fills the top of the loop and kills the prime.

If you need to cut the pipe to tighten the threaded connection, then I'd remove the loop and run it straight shot. Run to the ground or hang with straps. Add valves and unions at each end of both pipes. That way you can tighten again if needed. No DWV fittings. Add a couple of turns of teflon tape to the threads. Hand tight should be sufficient or lightly with a tool. Remember that tight is tight, too tight is broke! Don't crack the fittings.

 

[cfherrman]

Don't tape o ring sealed unions

 

[Fronzizzle]

Thanks for all of the replies! Just to provide a little more information:

1) There are valves at the filter end of both lines, I always use them when cleaning the filter or servicing it.
2) I suppose it could be for weight purposes, but he also has hangers and the overall run isn't that long so I'm not sure how much it would actually help

Anyway, when I go to fix the leak I'm going to re-run the pipes so they don't go over the deck joist. Thanks again.

 

[Fronzizzle]

Oh, I forgot something! Maybe this should be a new thread?

Anyway, at the pool end of both pipes the PVC ends 2-3' from the connections. Then, he has pool hose going from the PVC to the pool, connected with hose clamps. Is there any need for that? If I'm putting valves and unions at each end, can I eliminate the pool hose?

 

[cfherrman]

Yes do that, go hard PVC all the way. They probably did that for a flex joint but a long run of PVC has plenty of give in it plus it's strapped.

They were well meaning and did what they thought was right, which is better than doing cheap as possible and not caring

 

[Richard320]

Oh, I forgot something! Maybe this should be a new thread?

Anyway, at the pool end of both pipes the PVC ends 2-3' from the connections. Then, he has pool hose going from the PVC to the pool, connected with hose clamps. Is there any need for that? If I'm putting valves and unions at each end, can I eliminate the pool hose?

Maybe the skimmer and return have hose barbs?

 

[Fronzizzle]

I'll have to check when I get under there, but I think he put hose barbs on them - the return line is definitely normal PVC coming directly from the pool, he installed a hose barb fitting on it (this is the connection that has been leaking). I don't remember what the bottom of the skimmer looks like.

 

[Teald024]

Many of the skimmers and returns have threaded fittings. You should be able to unscrew the barb fitting and screw in a slip fitting.

 

[Fronzizzle]

I know it's been awhile since I updated this post, but the weather here in Michigan hasn't been cooperating.

Anyway, I can definitely do PVC all the way to the return line. However, the line coming out of the skimmer is hose barb, and it's part of the skimmer - no changing it. So, do I leave it and repipe it sort of like he had (skimmer --> hose --> hard PVC the rest of the way) or should I replace the entire skimmer?

 

[Richard320]

I know it's been awhile since I updated this post, but the weather here in Michigan hasn't been cooperating.

Anyway, I can definitely do PVC all the way to the return line. However, the line coming out of the skimmer is hose barb, and it's part of the skimmer - no changing it. So, do I leave it and repipe it sort of like he had (skimmer --> hose --> hard PVC the rest of the way) or should I replace the entire skimmer?

If you can find a hose barb the right size. just use it. Don't disturb the skimmer. It ain't leaking now, so don't provoke it. Keep the hose run short, but when you're planning things, allow room to replace the hose, or install a union somewhere so you can move the rigid pipes toreplace the hose if you ever need too.

 

[Fronzizzle]

Thanks!