Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Did my kid brother outdo me?

NickD on Sun March 14, 2010 8:41 AM User is offline

Told him I installed a new energy efficient furnace and seeing a 34% cut in my gas bill, by doing the work myself and with that tax credit only laid out about 900 bucks.

He went to a vertical geothermal system, something like this.



With four holes drilled a hundred feet deep, had it installed, would have to do the same, post digger only goes down maybe four feet, claimed after tax credits, cost him 14 thousand bucks. Also by installing electric efficient appliances, his electric bill remained about the same, but his gas bill vanished.

My last years gas bill was $1,526.00 for heating and water, he also got rid of his gas hot water heater in the process, anticipate this year if they don't go crazy, should drop to a thousand bucks. At that rate, if I could have installed a vertical geothermal system for $13,000 more, would have to wait 13 years to see a payback, providing the system doesn't require any repairs. My 13 thousand is still in the bank, but I didn't get any serious quotes around here, told it would be more like 25,000 bucks.

So who is better off?

Have to admit however, he is greener than me, except for his bank account. To be green costs a lot of green. My furnace has a full ten year warranty on all parts and a lifetime on the heat exchanger including all those sensors, blower motor. Forget about paying a guy 150 bucks to drive over, I have a screwdriver so don't expect to pay anything for the next ten years on maintenance.

Heard a rumor that refrigerants can leak out, not my concern, furnace doesn't use any. And who knows, what we are paying 3 bucks a pound for today could cost over a hundred bucks a pound tomorrow. Damn, I need a crystal ball.

FrankD. on Sun March 14, 2010 3:18 PM User is offline

Nick I think you won.

-------------------------
FrankD.

Karl Hofmann on Sun March 14, 2010 6:20 PM User is offlineView users profile

The ground source heat pumps that we use here use a form of antifreeze to flow through the ground loop and is then chilled in a packaged unit so there is a very small quantity of refrigerant in these systems.... Bore holes are dear to drill here, so if there is enough land, then we lay the ground loop about 1000mm below the surface, though you guys may need to lay yours deeper due to the colder Winters....

Click Here

-------------------------
Never knock on deaths door... Ring the doorbell and run away, death really hates that!

Edited: Sun March 14, 2010 at 6:25 PM by Karl Hofmann

NickD on Mon March 15, 2010 4:54 AM User is offline

Karl, you run a horizontal loop 1000 mm below the surface? Isn't a 1000 mm equal to one meter or a tad over 3 feet? We have to run our water pipes at least 8 feet below the surface so they won't freeze up, that's 2438 mm below the surface.

Didn't ask my brother what his geology is near Lake Michigan, we have eight feet of clay, 30 feet of sandstone under that, then granite as far down as you want to drill, did have a granite well 200 feet deep that cost me 3,000 bucks back in 1970, that would really cost today for drilling four holes. Brother tells me in his neck of the woods, horizontal systems quit working in around February so vertical is the only choice.

My son lives in an area of sand, helped him put in a point well, we got plenty of water at 8 feet down, but went down 20 using a rented air hammer to whack that pipe into the ground. He needs that for his water sprinkler system he has to run three times a day or else his grass will turn brown. That may be ideal for a horizontal system about ten feet down, depends on where you live.

Was thinking about an air heat pump to save a couple of bucks on energy above 40*F, lots of days like that, but that was even very marginal for payback. True, my AC system is over 25 years old now, but I maintain it, many of my neighbors replace their systems after five/six years, but they seem to have money to burn. If you have to pay a guy 150 bucks just to drive out a couple of miles than another 100 bucks an hour for them fooling around, cheaper to just replace the system. Know one guy that paid 600 bucks for new ignition module, another that said after eight years, his Lennox Pulse heat exchanger went out, paid 3,100 bucks for a new furnace. Said I thought your heat exchanger was guaranteed for life, he said it was, but the labor they wanted to change it, might as well buy a new furnace and get all new. I must be in the wrong business, but also getting a bit too old to crawl around.

NickD on Mon March 15, 2010 12:13 PM User is offline

Actually, if you have 14 grand in the bank, would lose about 4, 000 in interest earning over that period. If you get a second mortgage, would have to pay back that 14,000 plus another 7,000 in interest. Was talking about geothermal with my banker son that would also like to save money on energy cost and become green. He pointed out interest that I somehow forgot to add to the cost, may never get a payback, but you will be green in one way, greenless in another way.

bohica2xo on Mon March 15, 2010 1:29 PM User is offline

Nick:

You are aptly demonstrating the law of diminishing returns. Four 100 foot holes? lots of money there.

I have a 600 foot, 8 inch borehole on my property in AZ. Cost me close to 20k before they dropped a pump. The alternative was hauled water.

You would need a stack of permits the size of your car before AZ would let you pump anything DOWN that hole, and it better be safe to drink.

Of course the gas bill is not the issue out there. I had an unprotected cast iron pump freeze & crack the housing outside in the winter, but pipes 24 inches down do not freeze. Summer is usually manageable because of the latitude & elevation, but the swamp cooler works well because of the single digit humidity...

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

NickD on Mon March 15, 2010 7:34 PM User is offline

Haven't seen one bohica, but they are dropping in "U" tubes that form a closed loop system, then the tops of these U tubes are plumbed as shown here.



Assume they use some kind of anti-freeze for the media, but not sure unless the feed pipes are to the heat pump are buried using the same code as water pipes, about eight feet down below the surface. A pump circulates the coolant, so the coolant should always be at 55*Fm ground water that WI has plenty of should be a good thermal conductor. Home would only need a 15*F rise for 70*F with a good heat transfer, but more due to inefficiencies.

Sounds great on paper, until you considered the cost.

bohica2xo on Thu March 18, 2010 3:21 AM User is offline

Nick:

I can just hear the response from the state... You want to pump ANTIFREEZE into the ground!!!???!!???" Even a "U" tube would require a list of certifications as long as your arm, a leak sensor below it, and possibly a sampling bore they could access to test anytime they felt like it.

Which brings us to the heat transfer quality of the plumbing. To be acceptable for use in the borehole, it would need to be double walled - like .125 thick poly inside of .093 wall steel or some such nonsense. Unless of course you run potable water in the system...

Heck, the first 40 feet of the steel casing must be grouted in place - set in concrete. They drill a 16" borehole, fill it with concrete & slide 40 feet of 10" sch 40 steel (capped on the end) into the concrete.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

NickD on Thu March 18, 2010 6:04 AM User is offline

Tried doing some net searching on this subject, but not really extensive. A new way overpriced subdivision is going up in town that is claiming all their homes are using geothermal if they don't go broke first with the economy. No action in the last couple of years. I really don't know what they are doing, seems stainless steel pipe is in order for good thermoconductivity. Did contact three heating contractors in town, they said they don't install them, you will never get your money back. One really worked with me, so that is the one I purchased my new furnace from with a guy that can answer questions. They also do a lot of commercial work and were nice to give me free delivery and wrote if off as if they installed it for the full ten year warranty.

Will have to visit my brother one of these days and see what he has, what make, and who installed it. I do know our state has a super strict DNR, even made my kid with his point well we installed for his water sprinkler system to make sure his water was safe to drink. Although he is using city water for drinking, ha, his own water taste better but has to live by the code.

Back to Off Topic Chat

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.