Geothermal HVAC

[vetteman9368]

Anyone here have first hand experience with them? I have a client who wants to use it on his new build, and I've never been around them. Also thinking of using it on our new house nex year. I've read everything I can find, just looking for some first hand experience.

[DJ_Critterus]

Nope, but I did read that G.W. Bush has that going in his house in TX and it's supposed to work really well. It's much "greener" than Al Gore's house.

[78SA]

My parents had it. Paid for itself pretty quick. Super quiet too. No outside unit to mow around.

[Norm]

My son has one, my next door neighbor as well. As stated above, super quiet. Built in humidifier, seems like the temp setting never needs adjustment, stays a comfortable steady temp all the time, albeit a little pricy.

If I were to build new, that's the way I'd go.

[mrvette]

Got one here, put in by a p/owner some ~40 years ago, they dug a well down 30', which is not considered potable water, just like the river water at bottom of the hill in the swamp/bird sanctuary they call it....same elevation....so no loss there, what the well water does is act like a basically stable heat sink for the waste end of the heat pump cycle.....

now the system was really ancient by time I bought it, and it failed BIG time after about 2-3 years......went with a whole new system, but air/air heat pump outside.....RONG MOVE.....

it started to eat the outside coils from all the aluminum corroding because of all the overhanging acid in the damn oak/pine trees.....

so I had it converted over to water/air/geothermal and went back to the old type the house came with, the unit is FAR superior.....and cheaper to operate without that stupid defrost cycle the things have to do, to defrost the coils.....saving untold reverse cycle NOISE, and of course external/outside FANS noise, and the heat in the house is coming in over 100f and 55 or so in the a/c cycle....

1600' house worst case cooling was about 200 bux 100f outside FLORIDA humidity .....

last summer was hotter and worse yet.....worst bill 200 bux.....

BUT I cheated....painted my roof white, and dumped over 40f of attic heat load.....


:seasix:

[78SA]

My son has one, my next door neighbor as well. As stated above, super quiet. Built in humidifier, seems like the temp setting never needs adjustment, stays a comfortable steady temp all the time, albeit a little pricy.

If I were to build new, that's the way I'd go.

You can also replace existing systems with it.

[Norm]

You can also replace existing systems with it.

I just recently put in a $7K 20kW generator, one step at a time. :D

[Skia]

Got one here, put in by a p/owner some ~40 years ago, they dug a well down 30', which is not considered potable water, just like the river water at bottom of the hill in the swamp/bird sanctuary they call it....same elevation....so no loss there, what the well water does is act like a basically stable heat sink for the waste end of the heat pump cycle.....

now the system was really ancient by time I bought it, and it failed BIG time after about 2-3 years......went with a whole new system, but air/air heat pump outside.....RONG MOVE.....

it started to eat the outside coils from all the aluminum corroding because of all the overhanging acid in the damn oak/pine trees.....

so I had it converted over to water/air/geothermal and went back to the old type the house came with, the unit is FAR superior.....and cheaper to operate without that stupid defrost cycle the things have to do, to defrost the coils.....saving untold reverse cycle NOISE, and of course external/outside FANS noise, and the heat in the house is coming in over 100f and 55 or so in the a/c cycle....

1600' house worst case cooling was about 200 bux 100f outside FLORIDA humidity .....

last summer was hotter and worse yet.....worst bill 200 bux.....

BUT I cheated....painted my roof white, and dumped over 40f of attic heat load.....


:seasix:
Gene!! Do you EVER have a fcking thing EVER go right or just work with no stress?? :skia:

[mrvette]

Gene!! Do you EVER have a fcking thing EVER go right or just work with no stress?? :skia:

I knew going IN that the HVAC was old as the house....rocket science 101, and so my air/air deal not so hot.....move ON, with help from Linda's HVAC mechanic SON.....we got the job done....works fine.....

the thing runs so much less than the air/air system, what I save in defrosting winter coils, more than makes up for any additional amps drawn in summer....figgering in well pump at 3/4 horse vs 1/2 for the noisy outside fan....

:seasix:

[snide]

My next door neighbor has one. His heating cost is next to nothing. The propane provider was charging him $10 month for the tank rental simply because he wasn't buying any propane.

If you can afford to install the system during construction, do it. It will pay for itself. However, it is very costly to retrofit, and the ROI might not be worth it. That is, unless the costs have come down considerably in the last 5 years...

[Craig]

I've priced commercial systems, they're about a $2K per ton premium. It's got to be a similar cost for residential since the money is in digging the wells. If your load is five tons, how long does it take for you power bill reduction to equall ten grand?

[DJ_Critterus]

Gene!! Do you EVER have a fcking thing EVER go right or just work with no stress?? :skia:

No. If he did, why would he have a reason to live...nothing to post about :funny:

[justind]

I've priced commercial systems, they're about a $2K per ton premium. It's got to be a similar cost for residential since the money is in digging the wells. If your load is five tons, how long does it take for you power bill reduction to equall ten grand?

:iagree: We put one in a .gov building seems like a good way to end money to me. The extra cost sure does buy a lot of natural gas.

[78SA]

I've priced commercial systems, they're about a $2K per ton premium. It's got to be a similar cost for residential since the money is in digging the wells. If your load is five tons, how long does it take for you power bill reduction to equall ten grand?

Figure a minimum $100/mo savings. My parents house wasn't huge and they saved at least that much per month.

[mrvette]

I've priced commercial systems, they're about a $2K per ton premium. It's got to be a similar cost for residential since the money is in digging the wells. If your load is five tons, how long does it take for you power bill reduction to equall ten grand?

Jimminey Xmas, a 100' potable water well was drilled on my wife's 3 acres, feeds 2 homes there, and it ran like 1500 bux, can't see that even in expensive towns that it should cost like the same for a 'shallow well'.....

the unit itself is no different than a normal one, just using much smaller water/freon coils instead of the huge coil/fan setup, obviously you need a place to put the water after the unit is done with it, so we use it to irrigate the back garden,lawns with an option to run it down a drainage ditch straight down under the street to the swamp....:seasix:

[vetteman9368]

Jimminey Xmas, a 100' potable water well was drilled on my wife's 3 acres, feeds 2 homes there, and it ran like 1500 bux, can't see that even in expensive towns that it should cost like the same for a 'shallow well'.....

the unit itself is no different than a normal one, just using much smaller water/freon coils instead of the huge coil/fan setup, obviously you need a place to put the water after the unit is done with it, so we use it to irrigate the back garden,lawns with an option to run it down a drainage ditch straight down under the street to the swamp....:seasix:

The new systems are using a closed loop, no waste water

[Mike Mercury]

The new systems are using a closed loop, no waste water

yep. Co-worker just had this done; and it is closed-loop as well.

[Cybercowboy]

I remember my college Thermodynamics professor talking about this way back in the early 80's. He put one in at his house and was extolling the virtues of them. He used coils buried underground as the heat exchanger. We have very rocky soil here, it would take a well-engineered system to remain reliable.

[mrvette]

The new systems are using a closed loop, no waste water

Gotta dig up and bury about 1/2 acre or better of land, 3' deep, no???

cheaper to dig a shallow well, and water the land with it.....

:seasix:

[mrvette]

I remember my college Thermodynamics professor talking about this way back in the early 80's. He put one in at his house and was extolling the virtues of them. He used coils buried underground as the heat exchanger. We have very rocky soil here, it would take a well-engineered system to remain reliable.

The BEST thermal conductor for that would be copper too, THAT would run some bux.....I can't see using plastic, that would be nutz, .....:rofl:

[vetteman9368]

Gotta dig up and bury about 1/2 acre or better of land, 3' deep, no???

cheaper to dig a shallow well, and water the land with it.....

:seasix:

Nope, vertical ground loop 240' deep (here) one hole per ton.

[78SA]

Gotta dig up and bury about 1/2 acre or better of land, 3' deep, no???

cheaper to dig a shallow well, and water the land with it.....

:seasix:

Nope, vertical ground loop 240' deep (here) one hole per ton.

They can go either way. It depends on how much land you have.

[mrvette]

Nope, vertical ground loop 240' deep (here) one hole per ton.

HOW the hell they going down ~240 feet, then laterally, to lay pipe and up again to repeat the process??? the top joints are not all that much, but how do lateral joints on the bottom work out???

240' is down to the Limestone.....at least,

:waiting:

[vetteman9368]

HOW the hell they going down ~240 feet, then laterally, to lay pipe and up again to repeat the process??? the top joints are not all that much, but how do lateral joints on the bottom work out???

240' is down to the Limestone.....at least,

:waiting:

They don't go laterally, just down and back up

[mrvette]

They don't go laterally, just down and back up

SO, they drill a hole say 8" diameter, and drop this long U shape down there? and backfill with dirt/water till it's solid...??

interesting thought....but going through Limestone is getting pretty tough and expensive......:waiting:

[vetteman9368]

SO, they drill a hole say 8" diameter, and drop this long U shape down there? and backfill with dirt/water till it's solid...??

interesting thought....but going through Limestone is getting pretty tough and expensive......:waiting:

4" dia and 240ft is what they are doing here and it's one hole per ton. If you couldn't drill that deep, you'd drill more holes. They only have to be 10 ft apart

[mrvette]

4" dia and 240ft is what they are doing here and it's one hole per ton. If you couldn't drill that deep, you'd drill more holes. They only have to be 10 ft apart

I assume the pipes ARE copper, correct?? :waiting:

[Craig]

The BEST thermal conductor for that would be copper too, THAT would run some bux.....I can't see using plastic, that would be nutz, .....:rofl:

Typical systems are closed loop, and they use PEX in the wells. My in laws have one, they have a lot of land. Their system is about a thousand feet of horizontal buried at about ten feet. They also have it as a preheat for their domestic hot water. It's pretty slick.

[mrvette]

Typical systems are closed loop, and they use PEX in the wells. My in laws have one, they have a lot of land. Their system is about a thousand feet of horizontal buried at about ten feet. They also have it as a preheat for their domestic hot water. It's pretty slick.

I have to assume the PEX is loaded with water then and the system has similar coils to mine then, with a water circulation pump like that of a swimming pool.......

dummy ME is thinking the freon was going through the underground pipes....DUH.......:slap:

[benny42]

Gotta dig up and bury about 1/2 acre or better of land, 3' deep, no???

cheaper to dig a shallow well, and water the land with it.....

:seasix:

Pump and dump for comfort cooling is not legal in most of the country & not economical if the water table is lower than 25' down. :yesnod:

[benny42]

They don't go laterally, just down and back up

Laterals are done if you have a lot of land and the climate is moderate.

[xXBUDXx]

I assume the pipes ARE copper, correct?? :waiting:

Negative. PEX or a material that will transfer heat without corrosion from being direct buried. (See local code for an allowable material)

[C5Nate]

Uncle up at the farm in Northern Missouri has one that runs into his large & deep pond.

Its about a 5 acre pond that is 20+ feet deep near one end.

The pipe is buried underground about 4 feet and runs to the pond where 200” of coil is laying in the deep end of the pond.

Cut his electric bill on average $130.00 a month. Paid for itself in just 2 years.

Been in operation at least 20 years that I know of. He has had no major issues with it

[Craig]

We're currently building a hospital. The HVAC design is a hybrid of geo and evap. The geo field is just under $1M. Payback is eight to nine years.