NA - Geo Thermal Heat/Air Replacement?

AuntPeggy

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The house we bought has geo-thermal heat and air. It needs to be replaced. HVAC guy has been out every week this winter thumping, adding fluid, bleeding fluid, swapping switches, thumping, fiddling, and getting it to work about one week at a time -- then repeat. It has needed assistance getting going with each change of season for the last two years. Now, HVAC guy says they don't make parts for it anymore and whatever they do to fix it just barely works and there isn't much else he can do for us. It is somewhere in the neighborhood of 30 to 40 years old. There is only one company in town that works on geo-thermal. I called other firms, but they always refer me back to the original guy when I say it is geo...

Question: We're in our 60s and 70s. We intend to die here and then let the kids deal with selling the house. Installing a new geo-thermal will cost about $11,000 plus whatever unexpected costs pop up. New regular heat and air will be about half that. We like the idea of eco-friendly, but wonder whether we should go with the up-front cost. Probably won't pay back $6000 in utility savings in our lifetimes. Don't know whether it adds to property value, but as indicated, that's not my problem.

I'm asking for your knowledgeable opinions.

Thanks.
 
How significant is the utility savings? What climate do you live in?
 
How significant is the utility savings? What climate do you live in?

It's Oklahoma. :wink2:

Seriously, put in a new system and live comfortably, which will make it easier on your kids to sell after reading your will in another 2 decades.
 
I'm thinking you likely could nearly double your HVAC energy costs with an air heat pump versus geo. It really comes down to how long you will be in the house and if you can recoop the additional expense.

I'll tell you though, it sounds as though your repair guy isn't too good. There are only so many parts to replace and if you get it fixed right it should run reliably.

If the problem is with the tubes and hardware in the ground (leaking fluids) then you might be looking at more than quoted.


It's hard to say without more information.
 
I have a heat pump in my new house. Wish it was a geo-thermal heat pump. On the nights where it gets down below freezing, it runs all the time because the air is too cold for it to do much good.
 
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If the problem is with the tubes and hardware in the ground (leaking fluids) then you might be looking at more than quoted.


It's hard to say without more information.

Concur, get a second opinion. If the problems are above the ground, it should be able to be repaired. If the it's below the surface, I'd punt and install a normal system.
 
I'm pretty sure there is a significant bump in property value with a geo-thermal heat pump vs air heat pump.. people like the savings. It is also a much more effective heating.

Oklahoma gets pretty cold as far as I know, electric heat pumps aren't every effective below about 40F. Oil will work, but that's pretty expensive conversion and cost a bunch to feed. Gas would be ideal for the price if you have access to it.

On the other end, in the heat, geo is also more effective than running compressor for AC.
 
I'm pretty sure there is a significant bump in property value with a geo-thermal heat pump vs air heat pump.. people like the savings. It is also a much more effective heating.

Oklahoma gets pretty cold as far as I know, electric heat pumps aren't every effective below about 40F. Oil will work, but that's pretty expensive conversion and cost a bunch to feed. Gas would be ideal for the price if you have access to it.

On the other end, in the heat, geo is also more effective than running air compressor for AC.

Respectfully disagree...Some of the new air-to-airs will go well below 40F. We have one in the house we built 3 years ago. The reason I know that is that for the first winter, the auxiliary (electric) coils were shut off by accident in the set-up, so the heat pump was 'it' for heat. We went below zero a couple times... FWIW...

Jim
 
Respectfully disagree...Some of the new air-to-airs will go well below 40F. We have one in the house we built 3 years ago. The reason I know that is that for the first winter, the auxiliary (electric) coils were shut off by accident in the set-up, so the heat pump was 'it' for heat. We went below zero a couple times... FWIW...

Jim

True, new systems are much more effective and efficient.

I didn't mean to imply that they won't produce heat, just not as effectively as just about any other system.

In my, albeit small, gas heated house with a25 year old furnace I can shut off the heat for the entire day and come back to 50F inside the house(30F outside), turn on the heat and have toasty 76 in about 20 min. Air to air pumps have to stay running generally.
 
True, new systems are much more effective and efficient.

I didn't mean to imply that they won't produce heat, just not as effectively as just about any other system.

In my, albeit small, gas heated house with a25 year old furnace I can shut off the heat for the entire day and come back to 50F inside the house, turn on the heat and have toasty 76 in about 20 min. Air to air pumps have to stay running generally.
re

Agreed...and you DID say not as efficiently! You didn't say they wouldn't work!

Jim
 
re

Agreed...and you DID say not as efficiently! You didn't say they wouldn't work!

Jim



Just to be clear, I said "effective".. Heat pumps are actually thermodynamically extremely efficient. :) They use very little energy to perform the task. It's just that it's hard to extract any heat from a really cold air.

:yes:
 
What does your power cost? Low power cost and very cold temps make pure electric resistance heat cost less than heat pump.
 
I forgot to say that the house is total-electric. No gas lines, so we'd have to put that in if we wanted, which we don't so we won't.

What we have is a geo-thermal heat pump. It is way too old to be repaired, so that is what we are looking at replacing. The underground seems to be totally ok.

In summer, outside temperatures of 100*F are not uncommon. In winter, outside temperatures of below freezing are not uncommon, occasionally down to 0*. We set the thermostat for 80* in summer, 70* in winter and when the system is working, it handles that ok.

My electric bill runs about $150 per month, with a low of $91 and a high of $178.

The house is incredibly well insulated.
 
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I forgot to say that the house is total-electric. No gas lines, so we'd have to put that in if we wanted, which we don't so we won't.

What we have is a geo-thermal heat pump. It is way too old to be repaired, so that is what we are looking at replacing. The underground seems to be totally ok.

In summer, outside temperatures of 100*F are not uncommon. In winter, outside temperatures of below freezing are not uncommon, occasionally down to 0*. We set the thermostat for 80* in summer, 70* in winter and when the system is working, it handles that ok.

My electric bill runs about $150 per month, with a low of $91 and a high of $178.

The house is incredibly well insulated.


Those numbers really dont mean much....because the rest of your house can have one 60W lightbulb for the entire space or canhave 5000W flood lights every 2 feet. Do you have the manufacturer/model for the GSHP you have installed?

I'm a mechanical engineer that works on HVAC and plumbing. Granted, my work is pretty much in california, so I don't have a lot of experience with GSHP, but without looking at any numbers, I can hazard a guess and say that your average air-source HP won't be any less efficient than a ground-source HP from 40 years ago...
 
Get someone else to look at your in-ground system before you have him replace the unit itself. If your loops or wells are leaking, a new unit wont make a difference. The new systems are quite elaborate with their integrated controls.
Air/Air has picked up in efficiency. You would probably see a similar bill just with a new high efficiency air/air system.
 
This is much like dealing with maintenance when you own an airplane. Stop wasting money with guys who don't have a freaking clue what they are doing and are poking at it with a stick. Went through the same thing with three manufacturer recommended contractor before I found a competent group.

I don't know what kind of system you have (wells, horizontal ground loop, lake loops,...) but a lot of the cost is probably outside and not the problem. It's possible your heat pump inside evaporator/compressor is the problem but it's also problem that there's just a leak that the morons haven't diagnosed.

The sad fact is that Water Furnace who makes some of the best units has probably some of the WORST customer service I've seen in the HVAC industry. Fortunately, my local guys are top notch.
 
Oh, as for the local 'expert'. I had two different 'geothermal certified' hvac guys waste time and money without getting it right. Then I found the guy who installed it and it took him an hour to diagnose and fix the underlying issue.

HVAC techs get paid to upsell customers on new systems. I have encountered some ouright fraud trying to justify a new unit. Before you give up on what you have , get someone else out to check on everything to make sure you are. Ot being taken advantage of.
 
We had a fairly modern A2A heat pump at our cabin at Grand Lake, and it seemed to do okay once it got down to the freezing mark even though it seemed like it was running emergency heat (electric coil backup) fairly often on those nights in the teens and lower, and it certainly wasn't well-insulated being an older dwelling.

I think the value of geothermal helps a bit in resale value, but probably not enough to matter to most people in Oklahoma. Gas and electricity is just too cheap for it to matter. My 3K sq ft poorly-insulated home averages $50/mo in electricity and $175/mo in NG during the Jan/Feb months. I feel like it would be cost-prohibitive to install a new geo-unit for you, so I'd go with a standard HVAC/heat pump system if you can't find anyone who will/can repair your existing unit.
 
Geo = Ground source Heat Pump...

I was a contractor on a Mc Mansion 10 years ago. Customer had to have the latest /greatest , most energy efficient unit out there.. Can't remember the brand name ( somewhere in Minn) I think... The owner set the whole deal up..;);)

Anyway, he picked the open loop instead of the closed loop system,, Spent 25 grand on the system... Fought it one entire winter and it NEVER heated the house.. Manufacturer claimed it didn't need back up heat strips.. BIG mistake.... Finally the manufacturer did a onsite visit.... and finally admitted the unit would need ground water temp of at least 55f for a proper delta...

Water temp here is 45-46f year round....


Ripped the entire thing out and installed a Carrier NG furnace.... Another 18 grand...:rolleyes::rolleyes:.. And.... The entire unit was in the crawl space.... What a pain in the ass....:mad2::mad2:

Moral of the story.. If you use a quality unit and the ground source water temp is 58f and up.... it will be efficient..... Maybe.... IMHO..
 
The house is incredibly well insulated.

That's the key in all this. It's not the efficiency of the heating plant so much as the efficiency of the house surrounding it that can save money.

Jim
 
Are the costs you are looking at gross, or net of any tax incentives offered by the feds and/or the state? I believe geothermal installions qualify. Might be worth looking into.
 
The manufacturer is Friedrich Climate Master.
 
I can see the appeal of spending $5k versus $11k. And the point of a new air heat pump matching the efficiency of a 40 year old unit is probably right on.

It might be interesting to compare the system you have now (manufacturer and size) to what you were quoted now if you have that and want to share.
 
Geo = Ground source Heat Pump...
Watersource pumps are lumped with the geothermal, and even the ground source ones come in various loop arrangements. Mine goes down in a set of 380' wells. If you have the space you can run either vertical or horizontal looos.

Mine has not had any problems in nearly ten years of operation with making heat. What I've had:

1. Installation error were the attached radiant floor heat was misconnected to the wrong zones.

2. Installation error where the morons cracked the fitting on the exchange tank for the hydronic system which let enough air in the system to cause cavitation in some of the pumps.

3. A leak in the evaporator coil in the forced air system. I am guessing the duct guys put a screw through it though try as we could we couldn't find any evidence of this. Waterfurnace paid for it under the warranty.

4. The control panel on the hydronic system got progressively unreliable until it died.

5. The zone ducting was never installed properly though it took the guys fixing the evaporator coil to notice that it was hosed up. I just could never figure out why the temperature in that zone was goofy.

In all this only #3 and #4 are really part of the heat pump system per se. The rest as goofups of the bubbas who installed the related forced air and hydronic zoning.

The good thing is that the years I put it in I got a 33% tax credit on the installation costs. I don't know about the payback rate, but the nice thing is between this and the heavy spray foaming we run the entire house on about 6KVA (my generator reads out the load when we're off the grid).
 
A quick Google shows a 30% Federal tax credit for energy star thermal pumps has been extended through Dec31, 2016.
 
Watersource pumps are lumped with the geothermal, and even the ground source ones come in various loop arrangements. Mine goes down in a set of 380' wells. If you have the space you can run either vertical or horizontal looos.

Mine has not had any problems in nearly ten years of operation with making heat. What I've had:

1. Installation error were the attached radiant floor heat was misconnected to the wrong zones.

2. Installation error where the morons cracked the fitting on the exchange tank for the hydronic system which let enough air in the system to cause cavitation in some of the pumps.

3. A leak in the evaporator coil in the forced air system. I am guessing the duct guys put a screw through it though try as we could we couldn't find any evidence of this. Waterfurnace paid for it under the warranty.

4. The control panel on the hydronic system got progressively unreliable until it died.

5. The zone ducting was never installed properly though it took the guys fixing the evaporator coil to notice that it was hosed up. I just could never figure out why the temperature in that zone was goofy.

In all this only #3 and #4 are really part of the heat pump system per se. The rest as goofups of the bubbas who installed the related forced air and hydronic zoning.

The good thing is that the years I put it in I got a 33% tax credit on the installation costs. I don't know about the payback rate, but the nice thing is between this and the heavy spray foaming we run the entire house on about 6KVA (my generator reads out the load when we're off the grid).

I didn't know that.. I see the word Geo and associate that with Geology= Earth... I figured the other heat pumps were air to air transfer units...

This customer picked the open loop... First round was a disaster since he tied into the domestic well for water... Seems the unit ran constantly and burned out the submersible pump ( no drinking water, no flushing toilets, etc etc... Then installed a separate well for the heat pump.. Once they ripped out the POS, he converted the spare well for lawn irrigation...
 
I didn't know that.. I see the word Geo and associate that with Geology= Earth... I figured the other heat pumps were air to air transfer units...

This customer picked the open loop... First round was a disaster since he tied into the domestic well for water... Seems the unit ran constantly and burned out the submersible pump ( no drinking water, no flushing toilets, etc etc... Then installed a separate well for the heat pump.. Once they ripped out the POS, he converted the spare well for lawn irrigation...

There are at least three flavors:

- open loop: You pump up water from a well, run it through the heat pump and either pump it down into an injection well or discard it into the surface water (where allowed).

- closed vertical loop: You have a number of 'boreholes' which are wells that don't go into an aquifer, and contain a loop of PE tubing. Often the tubing is embedded in bentonite to increase heat coupling into the surrounding material. The loop is filled with antifreeze or brine and a system of pumps and a pressure tank maintain a closed and hopefully air-free system.

- closed horizontal loop: You have a number of ditches dug across the yard and the loops filled with brine or antifreeze are buried 8 or 10ft down. This works in places where you have a couple of acres of extra land and dont get extended deep freezes in the winter. As heat is extracted from the ground throughout the heating season, the loop temp tends to drop, at times below 30F. Of course, lower loop temps are going to adversely affect efficiency of a heat pump.

Other options include using lake or seawater in either open or closed loop configurations.


The advantage of the horizontal loop is that they are a lower up-front expense than having a well contractor drill at times several 200-400ft bore-holes. The downside is that you are dependent on ambient temperatures. Not as much as an Air-Air heatpump but still, once the loop gets really cold you may end up running backup heat for the coldest days of the year.
 
There are at least three flavors:

- open loop: You pump up water from a well, run it through the heat pump and either pump it down into an injection well or discard it into the surface water (where allowed).

- closed vertical loop: You have a number of 'boreholes' which are wells that don't go into an aquifer, and contain a loop of PE tubing. Often the tubing is embedded in bentonite to increase heat coupling into the surrounding material. The loop is filled with antifreeze or brine and a system of pumps and a pressure tank maintain a closed and hopefully air-free system.

- closed horizontal loop: You have a number of ditches dug across the yard and the loops filled with brine or antifreeze are buried 8 or 10ft down. This works in places where you have a couple of acres of extra land and dont get extended deep freezes in the winter. As heat is extracted from the ground throughout the heating season, the loop temp tends to drop, at times below 30F. Of course, lower loop temps are going to adversely affect efficiency of a heat pump.

Other options include using lake or seawater in either open or closed loop configurations.


The advantage of the horizontal loop is that they are a lower up-front expense than having a well contractor drill at times several 200-400ft bore-holes. The downside is that you are dependent on ambient temperatures. Not as much as an Air-Air heatpump but still, once the loop gets really cold you may end up running backup heat for the coldest days of the year.

This is the style we used.... I had a track hoe dig a 40'X40' by 20 foot deep hole, put is 3' of washed rock and made a loop of 4" perf pipe.. Basically a square drain field.... All we needed to do was shed 5-7 GPM..That part worked perfectly..
 
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Question: We're in our 60s and 70s. We intend to die here and then let the kids deal with selling the house.
I'm asking for your knowledgeable opinions.

Thanks.
I just wanted to say that when my Mother was around 68, she bought a new car. She said it would be the last car she ever bought. Six years later, she traded it for a more comfortable car with better visibility. She said it would be the last car she ever bought. Seven years later, she traded it for a car that got better gas mileage. Ok. That was the last car she bought as she had a fatal heart attack about six years after that.

My point is; don't predict your death too soon. You might disappoint your heirs and live longer than that.
 
I just wanted to say that when my Mother was around 68, she bought a new car. She said it would be the last car she ever bought. Six years later, she traded it for a more comfortable car with better visibility. She said it would be the last car she ever bought. Seven years later, she traded it for a car that got better gas mileage. Ok. That was the last car she bought as she had a fatal heart attack about six years after that.

My point is; don't predict your death too soon. You might disappoint your heirs and live longer than that.

:lol:
 
This is much like dealing with maintenance when you own an airplane. Stop wasting money with guys who don't have a freaking clue what they are doing and are poking at it with a stick. Went through the same thing with three manufacturer recommended contractor before I found a competent group.

I don't know what kind of system you have (wells, horizontal ground loop, lake loops,...) but a lot of the cost is probably outside and not the problem. It's possible your heat pump inside evaporator/compressor is the problem but it's also problem that there's just a leak that the morons haven't diagnosed.

The sad fact is that Water Furnace who makes some of the best units has probably some of the WORST customer service I've seen in the HVAC industry. Fortunately, my local guys are top notch.

Ron: are these "local guys" at your NC home, or in VA? We are building a cabin about 35 miles north of your Lake Norman home and am considering geothermal. Please provide me a contact if they are near me.

Thanks.

Wells
 
Hi,

I live in South Georgia close to the Florida line. Have open loop geothermal and it has worked great. Unit is down and as it is 30 yrs old I am replacing it with a new one. Quotes I am getting are all under $4000 for a 2.5 ton unit.
Same ducting of course, the open loop comes from the regular 4" well and discharges into a pond by the house. I had installed a tap to adjust the water flow easily, I just go for a 10 degree temperature change.

Heating with wood only until I get the new unit installed.

Ken
 
This is the style we used.... I had a track hoe dig a 40'X40' by 20 foot deep hole, put is 3' of washed rock and made a loop of 4" perf pipe.. Basically a square drain field.... All we needed to do was shed 5-7 GPM..That part worked perfectly..

In some jurisdictions with tight controls on water rights you are not allowed to discharge geothermal well water into the surface water but you are required to pump it back into the aquifer it came from. Of course, that drives up the cost of building the system.
A closed vertical loop system is isolated from the aquifer, you just dump or extract heat from whatever geologic formation surrounds your bore-holes. How much heat you can extract from each bore-hole depends on your local geology.
 
Although there are lots of posts here not many have addressed the OP's question.

Recommendations to fix a system that has exceeded its expected lifespan don't consider that even if it's repaired a terminal problem could come up soon afterward.

Aunt Peggy, you can install a conventional heat pump system and still meet your ethical goal of conservation. The systems available today are very efficient.

I understand spending the money to install a new geo unit is problematical because of age and limited resources. But you should consider the expense and its effect on your budget.

Given that conventional heat pump systems have become so efficient with two speed compressors and other features I think you can fulfill your goal of environmental responsibility and keep a significant amount of money in your pocket.
 
I am a bit surprised about the price of 11k to install a new geo unit. Assuming that your in-ground plumbing is intact and it is just an install of a new heat-pum, that price seems generous. Street price for a 2ton climatemaster is somewhere between 3k and 5k. Get a quote from a different installer on what they would charge to swap out the unit. There shouldn't be any electrical or plumbing work required. They may have to fit a set of hoses to connect to your fluid manifold and of course flush and purge the loops.

I recently replaced an Air-Air unit. The local utility had a cash credit that varied with the efficiency of the new unit. It may not apply to OK, but some states also have a state tax credit for installation of high efficiency equipment.
 
But the loop is 35-40 years old. Spending the money for a new geo unit while expecting the piping to last for another 10-20 years isn't realistic IMO.

If it fails, AP will be looking at another significant expense. That's another reason I recommend an air to air system.

As for AP's cost estimates, I assume they include replacement of the indoor unit too. It's 35-40 years old, it's an R22 system, and wouldn't be compatible with a new higher efficiency outdoor unit whether it be geo or air.
 
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Count me in two camps:

- $11K is whacked to replace the existing system, and the actual problem can't possibly be that big if it isn't outdoors.
- Newer Air-Air heat pumps are incredibly efficient, but do watch for contractors buying lower efficiency ones or lower quality ones to up their profits.
- I don't like that you say he's had a "burp" it, that indicates a leak somewhere. They need to find the leak.

ALL of the above lead to: Find a better HVAC contractor.

Neighbors did the Air-Air heat exchange thing with a high efficiency model, and it was blowing 90F air out of their heat exchanger when it was -10F outside. My HVAC guy was impressed even, and he installed it. :)

We decided to forego the Air-Air on our place when we upgraded the propane furnace and replaced the dead A/C unit... but the numbers *almost* worked for doing it.

Like you, we couldn't see recouping the capital expense, and without a tax credit, our propane system (which I realize you don't have) and our backup pellet stove easily handle heat duty very cheaply. Total HVAC cost for 2015 was $1015, and this place has pretty poor insulation, due to the top half of the house being a pre-fab built for a warmer climate.

Where you're at, I know you'd have to have A/C... and if the Geo-thermal underground water-based system is going bye-bye, you might as well do an Air-Air unit instead and make the unit do double heat and cooling duty.

Heck, done right, if the real problem can be found on the old system and it's not too expensive to fix with a contractor that knows what they're doing, you could have both...

(What can I say, I like backups... I'm a systems engineer...)

Depending on size/tonnage, expect to add about double the price of a straight A/C unit for an Air-Air unit in the total price for the outdoor portion.

Depending on your geekiness, I also highly recommend spending some extra bucks on the "smartest" thermostat system the new unit(s) manufacturer makes.

That cost number above? Automatically calculated by our 'stat with a recent firmware upgrade, and all of the data was stored on the manufacturer's server, so it calculated all the way back to installation, as soon as that code upgrade was auto-downloaded and installed via its WiFi connection.

Have an iOS App for both remote monitoring and control... four different time of day modes and full scheduling capability, changeable per day if desired, all the usual auto-switchover goodies and deadbands for those "in-between" months, the 'stat completely controls the variable fan and can be set for noise comfort or heating/cooling efficiency fan speeds, the 'stat can also act as a zone controller, and can handle multiple heat sources like Geo plus electric warmers, or even Geo plus gas... etc etc etc... the thing has been well worth the couple hundred bucks in the overall system install price.
 
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