Pool Cooling Advice with Booster Pump

[Gigem94]

Hello TFP Experts. I live in Houston and like many other have been trying to find a way to lower my water temps during the heat wave in an affordable manner, without too much uplift. I’ve researched a bunch on the forum and went down the aeration route and landed on the Kool Your Pool pool return aerator system. My results were actually quite good and was able to lower 94 degree water to 85 on overnight runs. The product works well.

My issue however is that I have old pipes and I started to develop leaks and my guess is due to the back pressure created when the aerators run. First one was the Stenner pump tube. A week later was the union joint at my heater. Then another at a repaired crack on an above ground return line that I marine glued. In short, fixed each leak, and I’ve stopped using the aerators b/c I don’t want to risk any more, especially underground.

I am not interested in a Glacier or Heat Pump as I like the aeration option because it’s affordable. I looked for a portable option and it seems only commercial options exist, and they are expensive, and spray a really long way.

That brings me to my next idea. I used to have a Polaris pump and cleaner and migrated to a robot a few years back. The pump died and I have the suction and return lines there. Would it be a good idea to install a new pump and put an aerator/KoolPool on the one Polaris return line so I can accomplish what I need? If so, can I just run the new pump alone or would I have to run the main with it? Would it still be too much back pressure?

Thank you for the feedback.

 

[ajw22]

I think the leaks are a coincidence with running your aerators. Use this as an opportunity to get your plumbing in better shape.

You Polaris pump did not use a suction line. It used a pressure pickoff from the main pool water that required the filter pump to be running when the booster pump ran. You cannot use the booster pump from that pickoff without the main pump running.

I doubt "back pressure" when running your aerators is causing the leaks.

What is your filter pressure when running the aerators and normally?

 

[Gigem94]

Pretty confident the leaks are because of the aerators creating more PSI on old glue joints/connections. Filter pressure is 20 PSI normally, and shoots to 30 with 3 aerators and plugs in.

Will the Polaris pump idea not work because the suction side is not strong enough on its own to pull enough water? If so would a stronger pump work better?

 

[ajw22]

Pretty confident the leaks are because of the aerators creating more PSI on old glue joints/connections. Filter pressure is 20 PSI normally, and shoots to 30 with 3 aerators and plugs in.

Where/why do you have plugs in?

Will the Polaris pump idea not work because the suction side is not strong enough on its own to pull enough water? If so would a stronger pump work better?

Those Polaris lines are small.

You cannot run two pumps off one suction line.

Where do you think the Polaris pump will get its water from?

 

[Gigem94]

Where/why do you have plugs in?

In order for the aerators to get enough pressure to throw the water, else it's just a gentle arc out of each aerator and increased flow to the other returns. I have 6 returns to the pool - 3 have aerators and 3 are plugged with their flow through plugs. Check this out: Frequently Asked Questions

Where do you think the Polaris pump will get its water from?

My plan was to only use the polaris pump at night solo to run the aerator. Daytime I'd run the main pump for normal use as I do today; so only one pump running at a time was the plan. Night time is when to run the aerators that I see the best cooling opportunity in my area.

 

[ajw22]

Do you know where the Polaris pump gets its suction water from?

 

[Gigem94]

Do you know where the Polaris pump gets its suction water from?

I do not. Is there any easy way to find out?

 

[ajw22]

I do not. Is there any easy way to find out?

Nope. Only by digging around the Polaris pipes and seeing where they go.

Usually the Polaris suction is connected above ground to the equipment plumbing before the return. In yoru case they buried it. Maybe it connects to the return pipe next to it. But I think you will see how there is no way the Polaris pump can suck water from that point int he plumbing without the main pump running to get water to where the booster pump pipe starts.

 

[Gigem94]

I called my local pool guy that remodeled my pool and asked him about this setup I'm asking about. He told me it would not work either. Mentioned the Polaris suction should be after the filter coming off the main return and to your point above says there is no supply unless the main pump is running, and the polaris pump is boosting the fed water when the main pump is on (which is why to run the polaris pump only when the main runs).

I appreciate the help in talking me through this Allen.

 

[mknauss]

Will that cooling device work off a sump pump flow?

 

[Gigem94]

I'm not sure as I do not know what the flow rate requirement is for it, but I am thinking maybe a 1/2hp or 1hp pump could run two of them at the long end of my pool and accomplish what I need and not compromise the existing plumbing. My plan is shifting to building a portable aerator unit and researching those elements.

Any thought on how I'd calculate the hp needed to run two of them with a water throw of about 12ft or so?

 

[mknauss]

I was thinking you would attach it directly to a sump pump outlet.

Only issue is sump pumps are designed for high flow but low head. I suspect that thing requires more pressure (head).

 

[Gigem94]

I just happened to have this pump in the garage, and the Kool Pool fitting had to be tweaked to fit the output. This is a 1/3hp.

 

[mknauss]

Looks like it works.

 

[Gigem94]

I need to go buy a lottery ticket

I actually have a second identical pump and will rig up another setup. I'll take some overnight temp measurements.

 

[Gigem94]

Loaded up 2 x 1/3 hp pumps with those attachments. Ran 8p - 730a. Start water temp was 93 finish was 88. Starting air temp was 92 with dew point of 75 and 58% relative humidity. Ending air temp was 78 with a dew point of 76 and 93% relative humidity.

I like the setup; my only complaint is the pump is somewhat unstable when running b/c of the water pressure which makes it top heavy. I'm concerned it might tip over in the night and drain the pool/flood the yard. Any thoughts on how I might stabilize them? Maybe a bucket with holes?

 

[mknauss]

If you can submerge the bucket so the water level is above the rim no need to have any holes.

 

[PoolFlunkie]

This is counter intuitive but try running the water spray during the day. I live south of Houston and this has worked well for me after some trial and error. The driving force for cooling the spray is water evaporation. The larger the difference between the air temperature and the dew point of the air is what drives the cooling. It’s similar to the way coolers that spray water into the air work better in dry climates than humid climates. The temp diff between the air and dew point is greater so the water evaporates and cools the air more effectively. My water temperature has been starting at 84 in the morning and it increases during the day about 3 degrees with the spray. (Without the spray it was increasing by 6 degrees or more until it finally stabilized about 95 with no cooling.) At night the water cools back to around 84 with no spray cooling. I assume this is due to radiation cooling and the dew point at night makes a significant difference here. I did run the spray for 24 hours a day for a few days and it reduced the temp only a degree or so more.

Anyway I’ve rambled but I hope I’ve made some sense. A real key to the cooling has been high water flow and small droplets. However if the droplets are too small they’ll blow in the wind out of the pool. I have about 25 gpm spray going from 8am to 8pm (I have modified it some to take pressure off the grid during the heat of the day). I use my normal circulating pump and installed inserts on the return outlets I’m not using for the spray that are 1/4” dia. The pressure going into the returns is about 25 pounds. I bought two fireman nozzles on Amazon to get high flow with a good spray. I hope this can help somebody. Cheers!

 

[colonelkirby]

PoolFlunkie, do you have pic of how you have the device all wired into your returns?

 

[PoolFlunkie]

I bought the fitting on Amazon and removed the spray bar and installed fittings to fit a hose. The spray bar didn’t do much. I had 3 of them but there’s not enough flow and they don’t make good droplets. They may work in a different climate but not in Houston with an extremely high dew point. Anyway I took out the spray bar and installed a 3/4” pipe section, coupling, 3/4 x1/2 slip x female pipe thread, 1/2 male pipe thread c male hose fitting. I tried some regular garden sprayers but not enough flow. Went to the fire hose fittings I got on Amazon and they work well. I used two of them and installed restrictions in the other return outlets (these were actually 7/8” rubber table leg covers that I had around and they worked well). A high flow is very necessary with a high dew point. I was able to get 25gpm with the fire hose fitting and about 5 or so otherwise. I attached pictures for all these things.