AC Units Cooled By Well Water

[PAUL J. MAGRONE]

I got a call from a guy about an inspection that I have set up for Wednesday afternoon. He states that there are 3 A/C units present, all original from 1980 something and that there are water hoses running from one of the wells on the property to the units. I am assuming this is a cooling set up but I have yet to inspect something like what he described. Has anyone seen this set up at an inspection that could give me some advice on things that I should be looking for other than the obvious. This guy is pretty cool and he understands that I am not an A/C professional but he would appreciate anything that I could tell him, other than the units are at the end of their expected life in years.

[Brian E. Kelly]

Are they swamp coolers?

[Marc D. Shunk]

"water cooled condensers". What you describe is what an hvac tech will know by slang as a "pump and dump" system. People nowadays favor calling it a geothermal system (that term might be more familiar to home inspectors), but it's essentially just a water cooled condensing coil versus the traditional large air cooled condensing coil. This may be straight AC, or it may be a heat pump. The quality of the water sorely effects the lifespan and the operating efficiency of the condensing coil heat exchanger.

[PAUL J. MAGRONE]

I believe that they are for cooling the units too. Thanks for the quality of water mention because I would not have thought of that. What would you suggest if these units are all functioning properly but he wanted to remove the hoses because they are above ground from what he is describing. These are old units but I want to advise him properly. What should I look for in inspecting the units other than operating them as usual?

[Charley L. Bottger]

Paul as Mark stated they are probably water cooled condensers from the well source but being the non-trusting sole that I am I do not necessarily believe what I am told by someone going on hear say. The units could also be glycol not likely but could be. I would determine the cooling medium on site. Water cooled condensers are high maintenance required to be acidized periodically to reduce corrosion if not, they will create high head pressure similar to a matted over air cooled condenser.

Its late had a 5k home with 4 A/C units and furnaces today Good night all and you too John Boy

[PAUL J. MAGRONE]

Thank you. I appreciate the heads up.

[Bruce M. Graham, III]

look here www.waterfurnace.com
could be water source heatpumps.

[David W. Shockley]

The new geothermal units drop copper pipe 300 ft in the ground where the base of the copper line has a torpedo shaped end. The refrigerant is cooled by the cold water that the torpedo is set in. I recently inspected/installed many of these units for Disney. They save about 70% on A/C bills. The old style geothermal used the actual well water while the new ones use the temperature of the water only. There were problems regarding the water quality on some older units in some areas of Florida. The cost for installing one is about $3000 more than an electrical unit. The copper lines run around $2200 alone. I am not sure of how it is hooked up but the geothermal units are capable of producing hot water for the home as well. Does anyone know how this works? The homes I inspected had small electric hot water heaters for back up only.

[Charley L. Bottger]

Originally Posted by dshockley

The new geothermal units drop copper pipe 300 ft in the ground where the base of the copper line has a torpedo shaped end. The refrigerant is cooled by the cold water that the torpedo is set in. I recently inspected/installed many of these units for Disney. They save about 70% on A/C bills. The old style geothermal used the actual well water while the new ones use the temperature of the water only. There were problems regarding the water quality on some older units in some areas of Florida. The cost for installing one is about $3000 more than an electrical unit. The copper lines run around $2200 alone. I am not sure of how it is hooked up but the geothermal units are capable of producing hot water for the home as well. Does anyone know how this works? The homes I inspected had small electric hot water heaters for back up only.

David that was the point I was pressing the cooling medium can and does vary between MFG's all doing the same thing changing the state of Freon from a hot vapor to a liquid does not matter how it is done. In my reports I just state the type of cooling medium and no way to do this unless on site.

As for producing hot water for domestic use, why not the compressor produces a hot vapor and could be routed through an heat exchanger designed for the use. I have not observed a unit of this nature but knowing the refrigeration principal I could trace the lines and tell you what was happening at the different stages and or configuration.

[Gary T. Heller]

Many years ago in Arizona we had a few residential package units with a device we called a pre-cooler. The idea was to spray water over the condenser to cool it and gain some saving from a compressor that didn't have to work as hard. I was never a fan of putting water on a DX unit coil for two reasons. First the water in AZ is very hard and it had a tendency to dirty up the condenser and the second reason was because I always felt the gas changed state in a different area of the condenser than it would with just air cooling. I don't want to get deep into thermo dynamics but if I ran across one now it would be interesting to see the condenser through a thermal imaging camera.

[Greg Bell]

Hi Paul,

I see these units all the time around here. They do last much longer than a unit that uses freon. They also have the added benefit of being a 24 hour a day sprinkler system. Most of these are also a package unit.

[Charley L. Bottger]

Originally Posted by gbell

Hi Paul,

I see these units all the time around here. They do last much longer than a unit that uses freon. They also have the added benefit of being a 24 hour a day sprinkler system. Most of these are also a package unit.

Hi Greg clue me in are you stating the units you see do not use Freon but water as the medium explain please.

[Greg Bell]

HI Charley

I was wrong.

http://cgi.ebay.com/CENTRAL-AC-Unit,...80822181r28423

http://images.google.com/imgres?imgu...IA:en%26sa%3DN

[Colin Cutler]

Hey Paul, Typically, you would have a temperture differential from your incoming water temp to your outgoing water temp. Depending on the water temp coming in I would think there is some type of regulating valve to restrict flow to get around a 10 degree differential, aside from that look for your differential in air temp.

[Charley L. Bottger]

Originally Posted by gbell

HI Charley

Yes they use water and not freon. Most of them that I see are over 30 years old.

http://cgi.ebay.com/CENTRAL-AC-Unit,...80822181r28423

http://images.google.com/imgres?imgu...IA:en%26sa%3DN

Hello again Greg
I am still confused what I was reading in your links just tells me that the condenser is water cooled not that the unit does not use freon. Have you actually opened up one of these units. Just trying to find out if someone else is using a system I have never heard of, still young enough to learn up here in the sticks
Thanks for your response