I have a natural spring in my back yard. The spring has a water temperature 45-50 degrees year round.
here is my idea I have a mobile home with a forced air system. I could us an air conditioning A coil and pipe the cool water from the spring to it would be gravity feed as the spring is at a higher elevation. The furnace is already set up to have an Air conditioner added to it.
I think that condensation may be a problem.
I may have to get a larger A coil as the temperature may not be cool enough.

Any thoughts or Input would be appreciated.

In large buildings they often use chilled water for cooling the air. ( we do it for the building and data center both. I think we also get hot water for heat. It all comes from a utility company that has lines run throughout downtown and you just tap in to it ) But i think it comes in far colder than you are talking. Almost freezing.

[This message has been edited by User00013170 (edited 02-15-2013).]

Nice idea. But your fears that 45 degree water may not do much are probably correct. I'm thinking you'll need a massive A-Coil, or several in line, to get serious performance.

But, then, if you're not looking to hang meat in there, it'll definitely help.

Dude, a waterfall in your house!
Keep cool, great sound, and scrub the air!

I'm a genous...genius.....awesome!

[This message has been edited by Boondawg (edited 02-15-2013).]

When I lived on the river one of the things that I wanted to try was pumping river water through a plastic pool solar panel inside my houseboat to see if it would cool a room. Those panels are really big water to air heat exchangers when used like that. You might need some kind of heat exchanger at the spring.

Research "Earth Tube cooling". There will be info on those sites about how to do it in water instead of underground.

Your idea is fundamentally sound, but I doubt that your spring alone will be able to provide enough cooling capacity. A good alternative to investigate would be a spring-cooled heat pump. It would probably provide all the cooling capacity you need, at somewhat higher cost than the spring water alone. With a heat pump, though, the spring can also provide a relatively efficient source of heat in the winter.

[This message has been edited by Marvin McInnis (edited 02-16-2013).]

You could do this, but it would not perform the way you would like. The big issue with this isn't the supply of water, it's the narrow temperature range you're working with. In a perfect world with perfect efficiency a reasonably sized heat exchanger would struggle to cool the air past 70 degrees. It would take a lot of air at that temperature to keep a home cool, and that's assuming no heat gain from duct work. Refrigerant is great for what it does, it provides a large approach temperature and a phase change which can transfer a lot of heat. Unfortunately it's very difficult to do the same with water. Also, what would you do with the water after it's passed through the exchanger? If it's downhill to your home is it uphill to return it to the stream?

[This message has been edited by mikejhjr (edited 02-16-2013).]

Most systems use a closed loop heat exchange. As water is pumped in a circular loop through a radiator placed in the spring and looped back to a radiator in the house. The spring water is only used as a heat sink. spring water is will average 54 degrees. It may not supply all the cooling you need but will reduce what you require from power produced cooling. Lots of factors involved. flow, refresh rate and how well the area you are cooling is insulated among other things.

Or use a better media than water in the closed loop.

The spring itself has a 1000 holding tank and the output is 1/2 of a 4 in PVC pipe nonstop it has never slowed down.
The used water would be returned to the stream

quote Originally posted by maryjane: Or use a better media than water in the closed loop.

Like Freon.

At 45 degrees, sounds like it would drop the temperature to a respectable level. You could install a valve on the piping to control the rate of flow, thus the amount of heat exchange. You might need a small inline pump to speed up the amount of water passing through if it doesn't cool enough. Passing the water back to the stream is good, since it hasn't been contaminated.

I'm guessing you have a down-draft central unit. Even an automobile radiator mounted into a box on top of the unit might give more surface area and better cooling. Though they didn't use it for cooling, I saw a mobile home up in the mountains near Knoxville, Tn. that used a spring up on the hillside to supply 24 hour running water to the house. One side of the sink was for household use like washing dishes, etc. That went to the septic system. The other side was plumbed separately and when water wasn't being used, the faucet was swung to that side. It was piped down to the barn where it provided water for the 2 cows. The overflow went to a pig pen trough, then that overflow was directed back to the stream.

Also, a local service station in the 50's had a wire covered box frame filled with wheat straw. This was mounted on the outside of one window and had a catch basin underneath. Inside the window he mounted a window fan. Water ran into the wheat straw from a pipe mounted across the top of the box. The fan pulled the air through the wet wheat straw and kept a store of about 1000 sq. ft. comfortable enough that it became a popular gathering place for his regular gas customers.

Did anyone say?
Swamp cooler.

We had one on the roof of our GM plant for something, not sure what it was but if you stood in front of it, it was like 20 degrees colder than the temp. next to it. I think that is what you are basically talking about.

Steve

------------------
Technology is great when it works,
and one big pain in the ass when it doesn't



Detroit iron rules all the rest are just toys.

quote Originally posted by maryjane: Or use a better media than water in the closed loop.

It's hard (or impossible) to find a safe and inexpensive liquid better suited to heat transfer (i.e. has a higher specific heat) than water. For maximum heat transfer, phase change systems (i.e. liquid->vapor, vapor->liquid) can't be beat, but that involves additional complexity.

[This message has been edited by Marvin McInnis (edited 02-16-2013).]

I hate to say it but this won't perform the way you'd like it to. To put it simply, the stream is just too warm to do what you want it to do. Even assuming 100% efficient heat transfer you would need a very large surface area in order to transfer the same amount of heat as even a 1/2 ton ac unit. And even if you had such a heat exchanger set up with sufficient cool water flow, which will not result from thermosyphoning, you will still struggle to cool the air past 70. And this is all assuming perfect heat transfer, not taking into account several factors which will greatly reduce the efficiency.

Sounds like it may be a good source to supply a Geo-Thermal heating and cooling unit.

http://www.youtube.com/watch?v=e1r7fXO0QII

Max

quote Originally posted by 84fiero123: Did anyone say? Swamp cooler. We had one on the roof of our GM plant for something, not sure what it was but if you stood in front of it, it was like 20 degrees colder than the temp. next to it. I think that is what you are basically talking about. Steve

Swamp coolers aren't a closed system. They trickle or mist vaper down a mesh of some kind, and the fan pushes relatively dry air across the water impregnated mesh. It uses that air's latent heat evaporation principle to cool the air as the water changes from liquid to vapor. I've seen some huge ones in warehouses, and they work great, unless you are 30' or more away from them. Smaller ones in small buildings and homes work so so in areas where the air is very very dry.

Why not just spray your ac coils and make them or efficient?
Well unless they are in the house then that would just be silly

Sounds like Mr. Ransom could have been the originator of the swamp cooler. It pretty much fits the description of what he used on his service station.

There is nothing wrong with geothermal done correctly, and that is what you are talking about. I know of no transfer liquid better than water that does not require far more complexity to use. Use the net, and do a little research. My sister-in-law uses the pond by her house to both heat in the winter and cool in the summer. She uses only minor help from heating and air conditioning the normal way to cover the differences.

quote Originally posted by Jake_Dragon: Why not just spray your ac coils and make them or efficient?

That can dramatically increase the efficiency of a closed-loop system for a while ... until the condenser coils become obstructed by dirt and minerals from the water. That's why systems that use water cooling towers always have a heat exchanger between the open-loop (and dirty) water system and the closed-loop (and clean) refrigerant system.

quote Originally posted by weaselbeak: There is nothing wrong with geothermal done correctly, and that is what you are talking about. I know of no transfer liquid better than water that does not require far more complexity to use. Use the net, and do a little research. My sister-in-law uses the pond by her house to both heat in the winter and cool in the summer. She uses only minor help from heating and air conditioning the normal way to cover the differences.

True in regards to good clean water, but spring water usually isn't "clean". More than likely full of contaminates, sediments, minerals, biologicals etc--all of which cause havoc within a closed loop system, especially when things percipitate out, not to mention it's relatively high freezing point.

What kind of GPM can you get going from the spring?

The HVAC evaporator coil will work, but I think you will have to cut the copper and plumb the pipes in "parallel" for maximum water flow.

Just some ballpark ideas:

a 3 ton AC unit is ~35000 BTU. (This may be super over kill for a mobile home)

That's ~10kwh, which means for a 10 degree C drop in temperature across your A coil (50F to 70F, maybe optimistic), means you need to feed it with about 1000L or ~264 gallons of water per hour.
http://www.engineeringtoolb...ge-water-d_1463.html

Water flow drops off significantly vs pipe length...... Find out how that works out vs. your change in elevation and pipe diameter and length here: http://www.calctool.org/CAL...vil/hazen-williams_g

There will be lots of added resistance in water filters, bends, etc, so take that into account.

It can be done. You'll spend $1000 on materials but never have to pay cooling electric costs again... Consider adding a valve/solenoid and running your thermostat to it vs. an AC unit. And filters. Lots of filters.

[This message has been edited by ryan.hess (edited 02-17-2013).]

I have both city water and a well. The well is also about 45 degrees all summer.

I run a hose to my outside air conditioning unit and drip cold well water down the cooling coils when the weather gets hot. I have not had any buildup of sediment over the past 5 years but it is a very good well. Prior to city water being available it was the water supply for the house.

This has considerably reduced the run time of the air conditioner is the summer months reducing my electric costs.

If I ever get around to it my next thought was to wrap the air conditioner compressor with copper pipes and run hoses and a small circulation pump to the pool. This will take the waste heat from the compressor (and cool it) and heat up the pool a bit.

what you are discussing is exactly what is used to cool houseboats. We pump water out of the body of water that the boat is in, run it thru an a-coil, and back to the river. then for the cost of running a fan to blow air across the a-coil, and a bilge pump, you cool the interior of the boat. Most boats are poorly insulated, and can still be cooled to a reasonable level with river water. that does not mean getting the interior down to 68 degrees because the river temp may not be that low. but it is a very efficient way to cool as you are not running a compressor. I would think with my experience with boats that it could be done with what you have to work with, My only real concern would be, how big of an a-coil you would have to have and if you have a sufficient supply of water. My guess is yes but you could not be sure without trying it. One more thing to think about is how far will you have to pipe the water? You may want to insulate the incoming water pipe to help keep it cool till it gets there.

quote Originally posted by agrabo85fiero: I have a natural spring in my back yard. The spring has a water temperature 45-50 degrees year round. here is my idea I have a mobile home with a forced air system. I could us an air conditioning A coil and pipe the cool water from the spring to it would be gravity feed as the spring is at a higher elevation. The furnace is already set up to have an Air conditioner added to it. I think that condensation may be a problem. I may have to get a larger A coil as the temperature may not be cool enough. Any thoughts or Input would be appreciated.

That would be awesome!

Like someone else on here said... a chiller system is really what you want. Sort of like a radiator system.

quote Originally posted by mferrell: btw when you run the water thru the coil you will be restricting the water flow so you may have to pump the water to maintain full use of the available water flow.

Pressurizing/pumping may increase the temp of the water a little.

What if you installed a radiant water cooling system in the floor?

How about you have a radiator in the spring, then have a radiator in your house, and then run lines to both of them and fill it with anti-freeze, and have an electrical pump push the anti-freeze around. That's all you need. Sounds ghetto, but they actually have a real system like that which you can buy for that very reason. In the north, the ground generally stays around 50 degrees about 8 feet down. So they have this very same system to bring the house to room temperature through all different seasons... 50 in the winter, and 50 in the summer... and then of course the normal air handler components with it's heating and cooling is used to adjust 10-20 degrees for your comfort... and it only turns on when you need the additional temperature. Obviously, when they shut off, the pump for the "heat pump" stops... so you're not heating / cooling the ground as well.