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Geothermal electric consumption?

P Dubya

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Last month my house used 6616 KW through the heating system, has never been that high. It was cold but not really colder than normal. System seems to run constantly once the temps get below16 -18 degrees. I think it is actually more efficient to turn the geo off and run only electric resistance. I called the installer and he is on vacation right now so will be next week before he cn look into it. Can anyone tell me what the temperature differential should be between the incoming and outgoing lines? Is a handheld point/shoot thermometer accurate enough to tell me anything? Thanks!
 
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Showkey

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Don’t know the numbers or costs .............but......Have a few friends with very expensive geothermal heat pumps that were installed to save money over propane ( when propane ski rocketed they were happy) ...........not so much now............one now uses the propane over the geo and one switch to NG when it became available.
 
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theoldwizard1

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One thing you need to monitor, at least occasionally, on any geothermal heat pump installation, is the temperature of the water going into the heat exchanger (the water returned from the geothermal heat sink).

If it is below 50F you might have an issue with the size of the geothermal heat sink. If below 40F, you DEFINITELY have a problem ! Likely it is undersized.
 

kwschumm

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I had a system where the ground loop actually froze the earth and lifted the soil where the loop was located. Loop temperature was -20 degrees.

Symptoms were unit running constantly, heat was inadequate, and energy bills sky high.

Dealer couldn't fix it, called WaterFurnace (manufacturer) and they arranged for a tech to check it out. Diagnosed a bad TXV valve, must have been bad from new. They replaced that, pumped up the system, the next winter it was much better but system still ran a lot. With the working TXV the system could deliver decent heat with a loop temp below freezing.

In this process I learned to test loop temperature and pressure. The loop is slightly pressurized (don't recall how much but not a lot) and our loop would leak down. So there was a leak in the loop.

Who the hell wants to dig up a ground loop to find a leak? So we lived with it, pumping up the loop once or twice a year. When the recirc pump went out the service tech discovered that one of the loop connections wasn't tightened enough when first installed and was leaking. Replace pump, connect it securely, pump it up and now the system was able to heat and keep bills reasonable.

Note that REASONABLE was not CHEAP, nowhere near the projected payback, and there is no way in hell I'd ever use one of those things again.
 
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P Dubya

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One thing you need to monitor, at least occasionally, on any geothermal heat pump installation, is the temperature of the water going into the heat exchanger (the water returned from the geothermal heat sink).

If it is below 50F you might have an issue with the size of the geothermal heat sink. If below 40F, you DEFINITELY have a problem ! Likely it is undersized.

Sounds like this is my problem... My thermometer probably isn't the most accurate but I measure about 33 degrees on one line and 43-44 on the other. The heated air temp at the outlet of the furnace is about 67 degrees. Thermostat at 69. Never warm enough to shut off....
 

yeldogt

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That's a lot of electricity -- how big is the house?

20 degrees was still the ideal low design temp when I last investigated -- that makes the return water in the low 50's. Now, not every system is going to be able to do that so the capacity has to be adjusted ... but the efficiency will drop off.

Seems to be a technology lag w/ Geo. But, I know that they have VS drive compressors now in some Geo systems .........so the ability to squees more out of lower temps is there .. just like the air to air. Once you get under 40 the older systems just fell off the map.

It's just a question of payback. With air HP systems now 3x less ecpensive to operate vs 20 years ago ... the overall costs of cutting that # in half w/ geo is harder and harder.
 
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P Dubya

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That's a lot of electricity -- how big is the house?

20 degrees was still the ideal low design temp when I last investigated -- that makes the return water in the low 50's. Now, not every system is going to be able to do that so the capacity has to be adjusted ... but the efficiency will drop off.

Seems to be a technology lag w/ Geo. But, I know that they have VS drive compressors now in some Geo systems .........so the ability to squees more out of lower temps is there .. just like the air to air. Once you get under 40 the older systems just fell off the map.

It's just a question of payback. With air HP systems now 3x less ecpensive to operate vs 20 years ago ... the overall costs of cutting that # in half w/ geo is harder and harder.

House is 2380 square feet on main level. Two bedrooms upstairs add about 600 square feet. Full basement but it has its own heat source. Small electric boiler for floor heat. I think the system/ground is likely near frozen. The geo system cant make an air temp above about 67 so obviously the system never shuts down. It has an electric resistance coil that is supposed to add heat when the geo system cant get the job done but I don't think it kicks in when needed. When I put the furnace into "Emergency Heat" mode it is resistance only and the air temp coming out of the top of the furnace is about 72-73 degrees... So far I am not terribly happy with the system. I grew up on wood heat that would leave blisters so I'm a bit underwhelmed...
 

jkeyser14

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You might be running in AUX heat (electric resistance heat) mode when it gets that cold if your loop was designed too small, but most likely is that your thermostat wasn't set up properly and is calling for electric heat when it can't meet the temperature setpoint quickly enough. To fix that you need to change the default amount of time the furnace will run in stage 2 before the electric heater turns on. Default is something really short like 5 minutes.

Is it a Waterfurnace brand or Climate Master? If it is a Climatemaster I can step you through the thermostat change you need to make.

My house is 3000 sq. ft, with our 4 ton geothermal system and average outdoor temps of 29 deg F our total electric bill for the last month was only $220.
 
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ddawg16

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I would assume if the aux heating turns on, it shuts down the geothermal loop.

What if the geothermal loop was still running while the aux heat was on? Would it be moving heat to the ground?
 

tgb

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With the strip heat running you should have air temp around 100 degrees at the register, do you have return air not panned off that you are pulling cold air from somewhere
 

jkeyser14

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I would assume if the aux heating turns on, it shuts down the geothermal loop.

What if the geothermal loop was still running while the aux heat was on? Would it be moving heat to the ground?

No, it wouldn't. The electric strip heaters are after the compressor, and the compressor discharge temps are normally around 85-90 deg. There is no chance the heat is going to ground.
 

850xpeps

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Does the system run in the summer a lot as well? I believe they have to return the heat to the ground so you can pull it out in the winter.
 
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P Dubya

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You might be running in AUX heat (electric resistance heat) mode when it gets that cold if your loop was designed too small, but most likely is that your thermostat wasn't set up properly and is calling for electric heat when it can't meet the temperature setpoint quickly enough. To fix that you need to change the default amount of time the furnace will run in stage 2 before the electric heater turns on. Default is something really short like 5 minutes.

Is it a Waterfurnace brand or Climate Master? If it is a Climatemaster I can step you through the thermostat change you need to make.

My house is 3000 sq. ft, with our 4 ton geothermal system and average outdoor temps of 29 deg F our total electric bill for the last month was only $220.

Neither of those.... Bard is the name on the unit. It seems like our houses are comparable size and I think my system has 6 loops/ton. I would have to look at pics to be sure. Last months bill was a bit over $500

I would assume if the aux heating turns on, it shuts down the geothermal loop.

What if the geothermal loop was still running while the aux heat was on? Would it be moving heat to the ground?


Yes, when I change the thermostat to Emergency heat the geo system shuts down.

With the strip heat running you should have air temp around 100 degrees at the register, do you have return air not panned off that you are pulling cold air from somewhere


I am measuring temp directly at the furnace where the ductworks takes off. 72 -73 degrees. I do not change anything else with the cold air return ductwork

Does the system run in the summer a lot as well? I believe they have to return the heat to the ground so you can pull it out in the winter.


Yes and it does a stellar job of cooling /dehumidifying during the summer. I spend my days outdoors at work so when I come home I like to have it like a meat locker.....
 

bsg

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Neither of those.... Bard is the name on the unit. It seems like our houses are comparable size and I think my system has 6 loops/ton. I would have to look at pics to be sure. Last months bill was a bit over $500




Yes, when I change the thermostat to Emergency heat the geo system shuts down.




I am measuring temp directly at the furnace where the ductworks takes off. 72 -73 degrees. I do not change anything else with the cold air return ductwork




Yes and it does a stellar job of cooling /dehumidifying during the summer. I spend my days outdoors at work so when I come home I like to have it like a meat locker.....

My system is 15 years old and is an open loop system, my house is about 2800 square foot plus a full basement.

You may want to have your system checked!
My air temp leaving the geothermal unit is 102!

I was having issues last year and had the unit checked, found a leak in the heat exchanger, now the system seems a lot more efficient?

We have been having a cold winter and our electric bill is only up slightly!

Kevin
 

jkeyser14

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Neither of those.... Bard is the name on the unit. It seems like our houses are comparable size and I think my system has 6 loops/ton. I would have to look at pics to be sure. Last months bill was a bit over $500




Yes, when I change the thermostat to Emergency heat the geo system shuts down.




I am measuring temp directly at the furnace where the ductworks takes off. 72 -73 degrees. I do not change anything else with the cold air return ductwork




Yes and it does a stellar job of cooling /dehumidifying during the summer. I spend my days outdoors at work so when I come home I like to have it like a meat locker.....

Call in a professional. That is not normal for a geo system to use that much energy.
 

yeldogt

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Something not correct .... my 5 speed Carrier does about 1500sf of the house ... and it used just under 500kw in January (so says the tstat)
 

TangoFoxTrot

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It just seems insane to me that a 2300 square foot house with GeoThermal is using over 6,600 kwh a month. I would think electric baseboard heaters would almost be more efficient.

Obviously somethings wrong, but curious how much electricity in the winter before the problem.
 

walta

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Check the temp of the supply and return air.

If the difference is less than 15° my wild guess is you have a refrigerant leak that will need to be located and repaired.

Count yourself as lucky as not all geo systems do not have emergency heat to use when the geo is down.

If the supply return difference is low run the E heat until you can get it serviced.

Walta
 
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P Dubya

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January bill was 3313 KW - .055 cents / KW
February bill was 6616 KW - .055 cents / KW
This does not include the power for lights etc.... That is separate and a different rate.
 
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tomroblee

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Your figures don't make much sense.

You say that the inlet water temperature is 44 degrees and the outlet temperature is 34 degrees. That is a 10 degree temperature drop.

A btu is the amount of energy needed to raise the temperature of one pound (pint) of water 1 degree.

For your size house, I am guessing that you have about a four or five ton unit with a circulating pump that has a flow of 10+ gallons per minute.

10 gallons per minute x 8 pints per gallon x 60 minutes per hour x 10 degree temperature drop = 48,000 btu per hour extracted ----which is in the range you would expect. If your air output temperature is only 67 degrees, what is the input temperature??? (the 48,000 btu extracted by the heat pump has to be going somewhere )

You say you used 6616 kwh last month which is about 220 kwh per day for a 30 day month. I can't imagine that your geothermal system could use that amount of electricity without having the electric resistance heat on for a material percentage of the time.

For some degree of comparison, I have a 3500+ sq. ft. house in central Indiana with 10' ceilings. The house and Climate Master geothermal are about 10 years old. The highest electric bill I have had in the six years I have owned the house was about 3200 kwh. My unit is a two stage and is located in my attic. It runs nearly constantly in sub freezing weather, but I assume that it is running on stage one a lot of the time of the time. My resistance heat kicks in with the heat pump still running and the outside temperature is in the single digits. In cold weather the water output temperature may be in the low 30 degree range. Based on the literature, the maximum electric draw is about 140 kwh per day without the resistance heat.

Based on the information you have given, it would be possible that your water circulating system is malfunctioning in some manner. (My 48,000 btu calculation was based on 10 gallons per minute or 600 gallons per hour. If your flow rate is only 60 gallons per hour, you would be extracting 4,800 btu.) It is also possible that you have a MAJOR leak in your return air ducting. A 67 degree output from your system is not reasonable if your return air temperature is only slightly lower. It would be very reasonable if you had a major hole in your return air ducts and you are heating 40 degree to 50 degree air.

You may or may not have an undersized ground loop. I would love to have a 55 degree water inlet temperature year round, and I could possibly achieve that by vastly expanding my ground loop at an exorbitant price. The alternative is to spend a modest amount on auxiliary resistance heat.
 

nine45s

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As a data point, I used 1800 kwh during the month of January, and it was a cold January with many single digit and negative degree nights. First stage ran pretty much constantly with the second stage coming on once in a while, third stage (resistance) never comes on.
I have a 4 ton Water Furnace, closed loop, 500 ft. of loop per ton. 1900 sq. ft. house with full basement, 17 years old.
 
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P Dubya

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Your figures don't make much sense.

You say that the inlet water temperature is 44 degrees and the outlet temperature is 34 degrees. That is a 10 degree temperature drop.

A btu is the amount of energy needed to raise the temperature of one pound (pint) of water 1 degree.

For your size house, I am guessing that you have about a four or five ton unit with a circulating pump that has a flow of 10+ gallons per minute.

10 gallons per minute x 8 pints per gallon x 60 minutes per hour x 10 degree temperature drop = 48,000 btu per hour extracted ----which is in the range you would expect. If your air output temperature is only 67 degrees, what is the input temperature??? (the 48,000 btu extracted by the heat pump has to be going somewhere )

You say you used 6616 kwh last month which is about 220 kwh per day for a 30 day month. I can't imagine that your geothermal system could use that amount of electricity without having the electric resistance heat on for a material percentage of the time.

For some degree of comparison, I have a 3500+ sq. ft. house in central Indiana with 10' ceilings. The house and Climate Master geothermal are about 10 years old. The highest electric bill I have had in the six years I have owned the house was about 3200 kwh. My unit is a two stage and is located in my attic. It runs nearly constantly in sub freezing weather, but I assume that it is running on stage one a lot of the time of the time. My resistance heat kicks in with the heat pump still running and the outside temperature is in the single digits. In cold weather the water output temperature may be in the low 30 degree range. Based on the literature, the maximum electric draw is about 140 kwh per day without the resistance heat.

Based on the information you have given, it would be possible that your water circulating system is malfunctioning in some manner. (My 48,000 btu calculation was based on 10 gallons per minute or 600 gallons per hour. If your flow rate is only 60 gallons per hour, you would be extracting 4,800 btu.) It is also possible that you have a MAJOR leak in your return air ducting. A 67 degree output from your system is not reasonable if your return air temperature is only slightly lower. It would be very reasonable if you had a major hole in your return air ducts and you are heating 40 degree to 50 degree air.

You may or may not have an undersized ground loop. I would love to have a 55 degree water inlet temperature year round, and I could possibly achieve that by vastly expanding my ground loop at an exorbitant price. The alternative is to spend a modest amount on auxiliary resistance heat.

Some more info for this reply.... It is a 6 loop system. Each loop is a 200 feet out and 200 feet back for a total of 2400 feet of loop in the ground.

I will measure the difference between return air temp and heated air temp after an hour or so. I just switched it from resistance to geo. It is much warmer today, maybe a high of 37.

Also keep in mind that the basement has its own heat system, small electric boiler with floor heat set at 67 so there is usage there but it should be constant.. the thermostat never gets changed. All the duct work vents that are in the basement are closed so the furnace does not heat the basement, I only use the ductwork in the summer to cool/dehumidify the basement.

Did I use resistance heat last month? Yes, the geo wont keep up so I switched over. Also keep in mind that I have an LP fireplace on the main level that is on every night just to add some heat to the house...
 

toyotadriver

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I know geothermal has advantages when designed and installed correctly but I've read so many stories like this one it makes me glad I went with an air source heat pump mated to a propane furnace. I looked into geothermal when we built the house and decided the extra cost wouldn't pay for itself in a reasonable time frame. We heat and cool 2450 sq ft and average monthly electric bill for entire house is below $90. We use roughly 800 KWH per month. We also use propane for hot water and cooking. We use about $25 or so of propane per month average (more in winter-less in summer).

We have much higher than normal insulation levels so that is a big factor.

If I was building again, I would always put more money into the insulation and less into the heating/cooling system.

Look forward to hearing what you find out is the problem.
 

jkeyser14

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January bill was 3313 KW - .055 cents / KW
February bill was 6616 KW - .055 cents / KW
This does not include the power for lights etc.... That is separate and a different rate.

Holy **** that is bad. You are using 3x -6x my normal usage for my entire electric bill. Call a professional in the morning.
 

theoldwizard1

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Call in a professional. That is not normal for a geo system to use that much energy.

Maybe not "normal", but very believable if the return water from the ground loop is too cold !

I dislike any geothermal system that relies on horizontal ground loops. They take up a lot of space and if the design engineer made a mistake in calculating the size required, your SCREWED :rant: !

At least with vertical loops (wells) it is possible to add another loop.
 

tomroblee

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I'm not a HVAC expert, but I like to think I have some common sense.

I tried to look up some specs on Bard geothermal equipment. About all I could find was some nearly useless ads on the Bard website and comments about the Bard company on other websites. It appears that Bard is an old, established family owned company. The general consensus is that Bard doesn't spend much money on making technical information available.

As far as your electric bill, the "small" electric boiler in your basement could be consuming a fairly large amount of electricity.

My house is built on a slab with the HVAC system and all ductwork located in the unconditioned attic. When I have ductwork leaks, they are all in unconditioned space. The way you describe your house, I am guessing that your ductwork is located in conditioned space. If so, it's hard to imagine how your return air temperature could be lower than the mid 60's ---unless it is somehow "sucking" air from an unconditioned source.

If you are sucking return air from an unconditioned source, your house would be pressurized and the excess pressure would have to go somewhere. The vent from your fireplace is one possible location.

I mention pressure because of a personal experience. A couple of years ago my electric consumption jumped greatly. I noticed that that aux resistance heat was kicking on when the outside temperature was under 20 degrees. I used an infrared thermometer to monitor temperature at various locations in my house. (It was a new toy and I was just playing with it.) I noticed that the temperature at my bathroom vent fans was very much colder than the surrounding ceiling area. This was an indication that I was sucking in cold outside air through the vents. I eventually found a monster leak in the hot air supply in my attic. I had been blowing heated air into my unconditioned attic ---which caused my house to de pressurize. The make up air was coming in through the bathroom vents.

It seems most electric companies are now going to "smart" meters and make hourly or daily consumption figures available on their website. It can be interesting to view this data.
 

jkeyser14

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I know geothermal has advantages when designed and installed correctly but I've read so many stories like this one it makes me glad I went with an air source heat pump mated to a propane furnace.

I just had a friend with a $800 bill last month for air source heat pump. It was running 100% electric resistance heat because it was <10 deg F for a couple of weeks straight and the heat pump couldn't work at those temps.

Also, the OP's problem is probably related to a compressor failure or refridgerant leak which is just as likely to happen on your air source heat pump as his geothermal.
 

kwschumm

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Maybe not "normal", but very believable if the return water from the ground loop is too cold !

I dislike any geothermal system that relies on horizontal ground loops. They take up a lot of space and if the design engineer made a mistake in calculating the size required, your SCREWED :rant: !

At least with vertical loops (wells) it is possible to add another loop.

This is the truth. We got into a tussle with our ground loop installer from out of state who was "the best guy in the US" according to Carlson's Heating in Kelso, WA. The tech suspected the loop was undersized and not built to spec. Loop installer sent us the specs he built too. Waterfurnace said there was no way to know for sure if the loop was adequate because it was built using a non standard layout that had no performance data available. We then sent it to a PE who was dealt with Geothermal systems and he said the same thing. No way to win that one.
 

clarky456

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I've failed to link a picture from imgur ( https://imgur.com/a/ilEay ).
To those that don't want to copy and paste, my geothermal saves me some money on electric!

Geothermal compressor wasn't working dec 18th through january 5th, bill doubled, with an electric meter read date the first of january. I burned nearly a cord of wood dec 23rd - jan 5th to help keep that electric bill down, otherwise wood is emergency only.

House was built in 2002, 2x6 walls, triple pane windows, 2500 sq ft and an oversized waterfurnace system equivalent to 6 ton, in service since 2002. May be upgrading soon, fed tax credit is back again.

Want my advice? Get someone out to look at the unit, asap.
 
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johnnyradiant

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.....
It seems most electric companies are now going to "smart" meters and make hourly or daily consumption figures available on their website. It can be interesting to view this data.

As an aside. A few years ago our province switched to smart meters. There were a significant # of people that saw their electricity bill jump. The old mechanical meters like gear driven clocks and watches slow down as they age due to wear and dirt build up on the gears. It's a win win for the utilities. They get more accurate data to bill you with, with a far lower manpower investment.

I wouldn't be surprised if the problem with the high consumption and low comfort doesn't turn out to be more than one cut and dried problem and some of it maybe the build specs of everything. A boiler in the basement will consume more in the winter especially if there are poor thermal breaks.
 

HoosierBuddy

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As an aside. A few years ago our province switched to smart meters. There were a significant # of people that saw their electricity bill jump. The old mechanical meters like gear driven clocks and watches slow down as they age due to wear and dirt build up on the gears. It's a win win for the utilities. They get more accurate data to bill you with, with a far lower manpower investment.

I wouldn't be surprised if the problem with the high consumption and low comfort doesn't turn out to be more than one cut and dried problem and some of it maybe the build specs of everything. A boiler in the basement will consume more in the winter especially if there are poor thermal breaks.

Yes. But what needs to happen is the utility needs to USE that data for more than billing. For instance, in the OP's case, smart metering would allow a "consumer friendly" PUCO (oxy-*****?) to monitor daily power usage vs weather data and, after a couple of days at most, send a message to the consumer saying "HOLY HELL DUDE! YOUSE USIN SOME SERIOUUUS NUMBER OF ERGs!", hopefully avoiding the 6 week traditional lag between something going wrong in an energy using appliance and the customer opening their bill for that period.

Back to the OPs issue, I'm really curious what you find out here. I don't work with geothermal, but I've heard these sorts of stories over the years, mostly when we have to do a quick natural gas install in the middle of winter, because someone has huge issue with a failed geothermal system.

Phil
 

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I dislike any geothermal system that relies on horizontal ground loops. They take up a lot of space and if the design engineer made a mistake in calculating the size required, your SCREWED :rant: !

At least with vertical loops (wells) it is possible to add another loop.

I have both on 2 separate systems.

The House system has 20 140 Foot vertical loops. Originally we were going to have 16 180 foot loops but we hit fractured bedrock at 140. So we added 4 more loops to get the capacity we need.

On my shop we tried the Vertical loops but hit fractured bedrock at 70 feet only 800 feet SSE of the house loop field. We ended up going with 8 300 foot directional bored horizontal loops. This is just as effective in my area based on a high water table. We bored at and average depth of 20 feet and were in water the whole time. Water has the best thermal transfer. If you run a horizontal loop in dry sand or clay you will have problems with thermal transfer.

One of the direction boring loops day lighted in the middle of the pond in front of the house.

If I had it to over again on the house system I would have directional bored the loops under the swamp behind the house. I believe this would be more effective than the vertical loops.

A properly design system will pay for itself. My shop is 10574 sq feet. I heat office and vault, 832 sq ft feet to 68°, the car shop, machine shop, storage room, and utility room totaling 4320 sq ft to 62° and the 5422 sq ft "Cold Storage" to 50° and the highest bill this year so far with how cold it got this year was $216. Last year the highest bill was $162 with a mild winter. Air Conditioning everything except the "Cold Storage" Area is more than effective. Averaging $37.00 per month in the peak of the heat. All these costs leave out the meter rental and service charges.
 

theoldwizard1

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If I had it to over again on the house system I would have directional bored the loops under the swamp behind the house. I believe this would be more effective than the vertical loops.
In your case, you might be correct !

I would want the horizontal portion of those loops under the swamp to be at least 50' deep. If they were shallow (20'?) there would be a possibility of freeze that wet ground from the surface all the way down to your loop.
 

tdkkart

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Something is wrong. Just as a point of reference, I'm in East central Iowa, my January bills, separate for shop and house, were the highest I've had in the 9 years we've been on this place, Our Febuary bills were substantially lower, so I'd say something went haywire in your system somewhere in that time frame.
 

toyotadriver

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I just had a friend with a $800 bill last month for air source heat pump. It was running 100% electric resistance heat because it was <10 deg F for a couple of weeks straight and the heat pump couldn't work at those temps.

Also, the OP's problem is probably related to a compressor failure or refridgerant leak which is just as likely to happen on your air source heat pump as his geothermal.



I suspect your friend doesn't have an issue with his heat pump. Assuming your friend's house is normal residential size, your friend's home lacks insulation.

That's also why I have a propane furnace. We can get some cold snaps but not for long. Electric resistance heat is expensive. It's really expensive if the house loses heat too quickly. MOST houses are under insulated....and that statement includes many new houses currently being built.
 

4 FN 27

ALLIANCE MEMBER
Joined
Oct 19, 2015
Messages
4,635
Location
Minnesnowta
In your case, you might be correct !

I would want the horizontal portion of those loops under the swamp to be at least 50' deep. If they were shallow (20'?) there would be a possibility of freeze that wet ground from the surface all the way down to your loop.

In our area the average frost depth under a road is 2.6 meters (8.53018 feet). Under sod it varies from year to year based on snow cover from 5.0 inches to 35.2 inches (thus 48 inch frost footing requirements on buildings in the area).

I doubt frost would get down to 20 feet. Otherwise Ice Augers would have 20 foot + drills on them and the ice fishermen would be limited to lakes with a greater depth than 20 feet.

The goal is to stay in the water table if at all possible. This is the most efficient means of thermal transfer.
 

Showkey

"MEMBER EMERITUS"
Joined
Aug 9, 2014
Messages
8,638
Location
Wausau WI
The goal is to stay in the water table if at all possible. This is the most efficient means of thermal transfer.


Which in some states or areas means another special permits that sometimes have serious restrictions.
 

jkeyser14

Well-known member
Joined
Dec 19, 2008
Messages
1,818
Location
(rural) Maryland
I suspect your friend doesn't have an issue with his heat pump. Assuming your friend's house is normal residential size, your friend's home lacks insulation.

That's also why I have a propane furnace. We can get some cold snaps but not for long. Electric resistance heat is expensive. It's really expensive if the house loses heat too quickly. MOST houses are under insulated....and that statement includes many new houses currently being built.

His home has plenty of insulation, but very few heat pumps will work in single digit temps.
 
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