Help me fix my pool circulation during renovation

[nostaljake]

See attached drawing! This pool was built in the 80s, and the locations of the returns has always seemed a bit weird to me. Circulation is a problem in a couple areas.

Note: the prevailing wind is from West to East, but (a) there's a lot of variability from day to day and (b) the house is very close to the pool and presumably blocks most of the west wind. So not sure how much this matters.

Anyway, I'm planning to renovate the pool soon! What additions / changes would you recommend to get better circulation in the pool? Would adding a return or two be enough?

 

[ajw22]

I would put one or two returns on each side of the spa so you get flow from one side of the pool to the other where the skimmers are.

 

[jonpcar]

@nostaljake, have you tried directing the returns you now have to manufacture a surface circulation swirl? My kidney shaped pool effectively uses only one return that accomplishes this.

It's worth a try before a remodel. Lots of threads on this topic, and many of them suggesting the use of ping pong balls to judge the effect. It took me awhile to make mine work with trial and error (I didn't use ping pong balls)... The rounded inside curves of a kidney shape pool can help this. I found the best result was to have the wall return point neither up or down, but so that the small surface ripples are seen only quite a few feet from the wall return itself.

Here's a guess on how you might be able to point yours to try and get a swirl started.

 

[nostaljake]

@nostaljake, have you tried directing the returns you now have to manufacture a surface circulation swirl? My kidney shaped pool effectively uses only one return that accomplishes this.

It's worth a try before a remodel.

Thanks for this post. I would LOVE to try to direct the returns, but they're 1" instead of 1.5", and they're non-threaded. I can't find any eyeballs that work. Tried one that you're supposed to suction into the pipe, but that didn't work either.

Anyway, the renovation is necessary regardless of the plumbing. But while I'm doing everything else, seems worth fixing up the circulation issue.

 

[nostaljake]

I would put one or two returns on each side of the spa so you get flow from one side of the pool to the other where the skimmers are.

Cool, something like this? And then pointing them clockwise sort of like @jonpcar suggested?

 

[jonpcar]

I think your placement is a good guess…from my personal experience, I like the left one a bit closer to the stairs and the right one a bit closer to the spa. But truthfully there are no guarantees and trial\error will be important (unfortunately after you have set the returns in place). Key will be having the ability to adjust the nozzle direction…it is very tough to get effective 90 degree returns (flow along the wall) and thus the benefit to directing them toward a further curved wall. You want your pump to run as low as possible (SWG/skimmer), in the 20%-35% range to make this work efficiently.

Personally I would really try to figure out something with the existing returns, it doesn’t necessarily take a lot of flow to start a swirl (two 1” pipes might do it). But, it sounds like you might have exhausted that possibility.

 

[jonpcar]

Jake, here is my pool. I have two returns and one skimmer. The arrow on the right shows my one effective return that generates the swirl.



The arrow on the left is my second return, it is directed down to the pool bottom back wall, otherwise it creates too much swirl and the surface debris simply bypasses my skimmer. It was definitely a trial by error sort of thing.

 

[nostaljake]

Jake, here is my pool. I have two returns and one skimmer. The arrow on the right shows my one effective return that generates the swirl.

View attachment 606928

The arrow on the left is my second return, it is directed down to the pool bottom back wall, otherwise it creates too much swirl and the surface debris simply bypasses my skimmer. It was definitely a trial by error sort of thing.

Thanks Jon! I see what you mean about using the curves. That makes sense.

For running the pump as low as possible, just checking you mean at a low RPM? Is that so the suction on the skimmers is reduced so they don't sort of overpower the swirl you're trying to create?

 

[jonpcar]

For running the pump as low as possible, just checking you mean at a low RPM? Is that so the suction on the skimmers is reduced so they don't sort of overpower the swirl you're trying to create?

No, running the pump at low RPM is just for cost reasons, but obviously only applicable to VS pumps. Once skimmers work properly, many run their pump continuously to keep the pool clean (and to also generate chlorine with a SWG)…particularly during swim season. At 1000rpm (assuming about 200watts), that’s less than 5kWh/day to run it 24/7. For me, that’s ~$20/month.

Suction on the skimmers is good