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AC Units Linked w/Evaporative Coolers

AC Units Linked w/Evaporative Coolers

AC Units Linked w/Evaporative Coolers

(OP)
I'm sitting here listening to my residential AC running and wondering why there are no swamp cooler pads pre-cooling the air before the air is drawn thru the condenser. Or maybe just very low gpm misters that cool the condenser directly with water. Am I missing something? It seems so simple - is there a practical reason why this is not done?

RE: AC Units Linked w/Evaporative Coolers

I have a friend that has just a system.  A water fed mesh pad on the condenser inlet.  Unfortunately he lives some 500 km away so I can't run out and get a name off of it.  BUT, your question has set met thinking and I might just pursue it for myself.

rmw

RE: AC Units Linked w/Evaporative Coolers

(OP)
Thanks for responding rmv. I live in Oklahoma,USA and 105 degrees F will not be unusal in the coming weeks. Your comments give me some encouragement that this idea is not a dead end. I am retired, but I am a inveterate tinkerer. I am going to do some tinkering and testing. I'm figuring that I cant hurt anything.

RE: AC Units Linked w/Evaporative Coolers

what you are describing would be a water cooled cooling tower.
You don't do that in residential or small commercial appreciation because maintenance is horrific and only worthwhile when large application.

Staff grows in warm water, it needs to be winterized when freezing, corrosion... all things only worth to overcome when the plant is large.  

RE: AC Units Linked w/Evaporative Coolers

I have seen sprinklers run on condensing units to help cool on hot days - basically the system was undersized.

what they found in the long run is that all the minerals in the water came out solution on the condensing unit fins restricting air flow and making it worse.  

a pad may be different than water directly on the coil though.

 

RE: AC Units Linked w/Evaporative Coolers

If you're going to run a swamp cooler, why not run it on the evaporator?

It will reduce the load the same.

 

RE: AC Units Linked w/Evaporative Coolers

Evaporative coolers work really well in the Southwest where we see average relative humidity numbers less than 30%.  I used to live in Oklahoma and I don't think I ever saw a cooling-day humidity less than 70% RH.

Here in the SW, we regularly see a swamp cooler drop air temp 20[°]F while raising relative humidity from 20% to 50%.  I would expect in Oklahoma to be able to get a 6-10[°]F temperature reduction while taking humidity from 70% to 85%.  Temp drop would be less on a 85% RH day.  So, with air at 105[°]F and RH at 80%, your hard work would lower the cooling-tower temp to around 102[°]F.  That may be worth it.  It probably isn't.

In a lower humidity area, it could very well be a great idea to have a swamp cooler feed air to a ducted cooling system.  I don't think that Oklahoma would be a great place to start.

David

RE: AC Units Linked w/Evaporative Coolers

The idea would work fine if the RH is low (around 20 ~ 30%) on cooling days with high outdoor DB temps. We do this on Big Chillers here in some parts of India where the summers are dry.The only thing to keep in mind is that the Condensor Fan must be able to overcome the increased static. You don't want to end up with a fan motor burn out.
 

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