I could use some thoughts/input into a home cooling project that hopefully will eliminate the need for using the air conditioner in my house. We live in Virginia, so the sun exposure is from the south and the
My wife and I bought a house six months ago. It became immediately apparent that there are two climate zones in the house. The foyer and upstairs are the first climate zone. The foyer is the entry point, and the entire length of the room is southern (solar) exposure, which means it gets very warm. The foyer has vaulted ceilings, and is completely open to a good portion of the upper level. It gets a lot of heat and passes it all on to the upper level of the house. The upper level has its own southern exposure, and just by the nature of warmer air rising, it gets HOT! Right now we spend basically all our time on the upper level. The kitchen, living room, dining room, bedrooms, bathrooms, office, and washer/dryer are all on this level. We hit 90+ degrees this last weekend on the upper level of the house.
The downstairs has no southern exposure at all. Most of the southern exposure is under ground level. This level is probably a good 15-20 degrees F cooler than the upstairs. There are three large rooms and a crawl space down here (under the foyer, you can walk if you stoop a little). The furnace/fan is located in a room that is open in back to the crawl space. This last weekend the downstairs felt wonderfully cool compared to the upstairs, and that is entirely due to the nature of shedding heat to the underground areas and lack of southern exposure.
I hate using the air conditioner. It is a nasty energy hog and there are many natural alternatives if you plan well. I have found some inspiration in the
Earth Tube concept. I think I can use the floor in my crawl space for a
closed loop design. I want to install an air intake in one of the lower level rooms that backs to the crawl space, and install a low power fan connecting to duct/piping that I will bury under the ground in the crawl space. the duct/piping will be run back and forth all the way to the furnace. There are three air returns in the house, two at high points and one at a low point. I want to re-rout the duct that draws air from the high points in the house into my earth tubes so that the fan will push cold air to the highest points inside the house using those return vents.
Here is a schematic of what I am thinking. The new piping is in blue.
Those high point returns are only needed when air conditioning the house because you want to cool the warmest air, so if i cut them off it should not affect the home heating during the winter months because you want to draw the low point cool air at that time of year anyway. I will also need to make sure that condensation can drain out of the duct/pipes in order to prevent moisture from building and mold from growing. I plan on laying the duct/pipe on top of a gravel bed and making drainage holes all along the underground portion. I think that will provide enough drainage to keep any condensation from creating mold issues.
My questions/request for input:
- Is there something I am not thinking of?
- What are some possible unintended consequences?
- Should my fan push cool air to the high point of the house or pull hot air from the high point and cool it?
- Is my drainage/condensation solution adequate?
If this works right the AC should no longer be needed at all so cutting off those upper level return vents should not pose a problem. I might use copper pipe (
$$$) for the germicidal and heat conducting properties despite how expensive it is. I'll also be using anti-microbial air filters at the output of the system, whether that be at the upper points or lower points. I will lose efficiency, but I have a 5 month old and will take no chances when it comes to mold/fungus growth.
So, what are the thoughts on this?
