Author Topic: Earth Air Tubes Completely Cool a Home??  (Read 4654 times)

0 Members and 1 Guest are viewing this topic.

clone477

  • Newbie
  • *
  • Posts: 14
Earth Air Tubes Completely Cool a Home??
« on: October 05, 2005, 10:33:37 PM »
Hello everyone,  Ive spent the last week staying up to around 3Am just reading all the good info on this site.  Im very interested in making an earth tube system in a closed loop design.  I partically like this design http://www.mb-soft.com/solar/intake.html.  My question is will these systems if properly sized/oversized, completely eliminate the need for ac in the summer months??  Ive read mixed reveiws about this.  I know my ground temps for my area is around 8 degress C year round.  And summer temps are usually between 25-35 degrees C.  I know that it will not completely heat a home.  I also really like this design because it doesnt need a  heat pump, fluid, any maintanace at all.  Just the mold concern which I dont think will be a problem.  Thanks for any advice on this guys.  Fern.
« Last Edit: October 05, 2005, 10:33:37 PM by (unknown) »

BoneHead

  • Newbie
  • *
  • Posts: 34
Re: Earth Air Tubes Completely Cool a Home??
« Reply #1 on: October 05, 2005, 06:37:48 PM »
By "earth air tubes" I assume you mean geo-thermal heating and cooling. On the site you posted a link for, they suggest using pvc pipe. If you bought enough of it and dug enough of your yard up, it would work, however, if you could come up with some large metal tubing and paint the outside with asphalt paint it would work much better because the metal would conduct or loose heat a lot quicker than pvc.


The thing you would have to keep in mind is that pvc is a little bit of a temperature insulator. It's not an efficient insulator but it does have that quality to some extent. So, you would have to make sure that you were not pumping the newly taken in air into your house before it had a chance for the temp of it to be lowered to the desired temp. There would have to be a great deal of length to it to ensure this.


I have looked a lot into stuff like rammed earth and straw bale construction. It's the same concept really. The rammed earth or straw bales are huge insulators like the ground itself. There are two straw bale homes in northern florida that maintain a temp of about 75 year around. That's pretty good but outside ventilation will change it drastically. It's the same with the pvc. If your taking the air out before new air has a chance to be altered to the ground temp. You said you were thinking about a closed loop system. Without filtering, you should be aware that any moisture or unwanted smells will remain for a long, long time as it is pumped continually in and out of your house.


Yes, geo-thermal cooling is more efficient that central due to less power being used and if you can go that way, I would. At the same time, it may be a smart thing to purchase $100 worth of thin wall pvc, rent a trencher and try it out somewhere that you can dig up and no one will mind. Hook a blower to it after the air inside cools, then time how long it takes for the air to get warm again. Record that time with the pipe length. Then shut it off and give it a minute or two. Turn it back on and see if there air has cooled yet. If it hasn't, do it again but wait a bit longer. Keep doing this until you have determined how long it takes the air inside the pipe to cool. You'll need those numbers for determining the length of your system and the power of the blower system you use.


I would much rather spend $200 and waste 5 or 6 hours of my time than buy $1000 worth of stuff that wont be satisfactory for the job.


Also, unless you have a central blower location in an area that can be used as an air well, you will have to have several smaller in-line fans (w/ separate motors).


If you can do all that stuff, I would do it. I have a lake right next to my house and I was actually thinking of running a line of pipe underwater to get my AC...lol.


The only thing that bothers me about it is that they suggest pvc and they only say 4". It may very well work though.

« Last Edit: October 05, 2005, 06:37:48 PM by BoneHead »