Michigan Building a New house and looking to install geothermal

Discussion in 'General Discussions' started by Thomas G Strasser, Jan 11, 2019.

  1. Thomas G Strasser

    Thomas G Strasser New Member

    Hi all,

    New to the site, New to geothermal, and new to new house construction.
    I have searched here for information on new consturction installation, and I must admit that I am not the best searcher in the world, so this maybe covered.

    The wife and I are building a new house in Bloomfield township Oakland county Mi. I have had a passing interest in geothermal, and figured I'd look into it for the new house.

    From what I have read and seen, most people seem happy with the systems. Two people I know in real life have the system. Person one had their system installed into a 100 year old farm house and is quite happy with it. It is a vertical closed loop system. My other contact with geo has a closed loop pond system and likes the cooling, but isn't overly thrilled with the heating aspect.

    My property will have well water and a septic system (not important here really), and I was interested in an open loop system. I have about 1.5 acres of land, the house will be a single story about 2000 sqft. with a walkout basement.

    I will have the system professionally installed, so I am in the process of getting quotes for it. I found a couple of vendors on this site and others form an internet search.

    i have seen a lot of info both here and on the internet. Most info on the net gives basic discriptions of how the systems work. this site is the first place I found that has actual real life experience.

    With all that being said, can you all give me all the information on the pros/cons, what I should know and what you all learned after the fact. A kind of leassons learned report.

    Cause really I don't know what I don't know

    Thanks
     
  2. nc73

    nc73 Member Forum Leader

    Before you consider open loop, get the well drilled first and check water quality/quantity.
     
    Thomas G Strasser likes this.
  3. Stickman

    Stickman Member

    Welcome Thomas!

    I formerly used oil for hot water baseboard heat and hot water. I now have a closed loop water-to-air system.

    Pros: Not having to worry about fluctuating fuel prices, deliveries, maintenance scheduling and servicing, chimney maintenance. Having flame-free heating gives me peace of mind from a safety perspective. Closed loop hasn’t required any fluid to be added or maintained. I leave the set temp alone (no setback), and am comfortable. Overall about 30% savings with electricity as my “fuel” versus oil. 5 years in and no problems or service calls. I change filters and monitor the system’s operation.

    Cons: Not as many qualified installers/servicing companies as I’d like to see. Had to become very hands-on to verify that my system was operating as well as it should, and to verify it continues to do so (through monitoring). But have received great support from the members here.

    Overall I am happy I had geo installed.
     
    Thomas G Strasser likes this.
  4. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    What is wrong with a horizontal closed loop system? Not as expensive as drilled....

    I only put open systems in when I have to.....more trouble and higher maintenance.....
     
  5. Thomas G Strasser

    Thomas G Strasser New Member

    I was looking into an open loop system for 2 reasons, one was cost of install and since I will have a well it kind of made scense. As I read more and more on it, I can see that there are hidden costs in it. buildup of minerals in the pipes for one. Talking with the township and the county, they do not seem to have an issue with an open system with or without a recharge well, nor the volume of water required (1-3 million gals/year). It also seems that open systems may not have the ability to heat or cool as well as a closed loop. The one sales/installation company that has replied so far said I do not have enough land for a horizontal system (approx 1.5 acres)
     
  6. nc73

    nc73 Member Forum Leader

    I did notice going from open loop to closed, it was almost like losing a stage. It was accounted for when I sized the heat pump. It will run longer with closed loop vs open, in the end I used almost the same amount of electricity with my 3/4hp water pump in open loop vs closed loop with single 26-99 on low. I will need heat strips when the temperature dips to negative F.
     
  7. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Well...Heat capacity is higher at warmer entering water temps. however, you spend more pumping power, have less maintenance.

    If someone tells you that 1.5 acres is not big enough, you should no go with them. A 5 ton heat pump is usually supported by a 70x70ft horizontal loop field.
     
    Thomas G Strasser likes this.
  8. Thomas G Strasser

    Thomas G Strasser New Member

    Thanks for that info, I was kind of set back when they said I couldn't go horizonal
     
  9. Eric Kurtz

    Eric Kurtz Member

    Wow! I've got 3 ton in an area 70' x 330'. 2800' of 3/4” straight pipe on 10' center. I was trying to keep EWT closer to 40* and with unlimited space and DIY, I decided why not.
    How many feet of pipe would you have in that space, doc?
     
  10. Eric Kurtz

    Eric Kurtz Member

    But even at 70' x 330' is still just a bit over 1/2 acre.....
     
  11. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    7 slinkies 600ft each, 65ft trench, 3 ft wide, 10ft of center. 4200 ft pipe
     
  12. Thomas G Strasser

    Thomas G Strasser New Member

    Thanks all for the info, the quote I am looking at has the horizontal system in a 40'x 130' whch should be no problem on the property.

    Looking at the all the cost and since this is a new construction, in the semi DYI frame, if my builder was willing to install this, (he already has HVAC budget (not geothermal) along with plumbing and electrical. He is going to dig the basement hole and everything. would you guys think that this would be a good idea?
     
  13. Timothy Fossa

    Timothy Fossa New Member

    I have a SCW Geo system in Vermont off the house water well pump and it works like a top. But it's in hard rock (top soil is the other guy's problem :)). If you go the SCW route make sure the well is initially drilled deep enough to support the heat pump size. While you're doing the new house; also pay attention to insulating the building envelope above the minimum. There are nice R4.5-5 windows out in the market now. Much better than what is needed to meet the minimum energy star rating. R60 in the ceiling. R20+ in the walls and under the basement floor. You might also look at mini-split systems with a cold weather package if your area doesn't get outside their performance range.
     
  14. wing

    wing New Member


    i love these closed loop design threads. and well done so far to you.

    is there any detail you can give us on your closed loop design in 40' x 130' area for 5T heat pump.

    drawing welcome

    thanks
     
  15. Rogerthat

    Rogerthat New Member

    Hi Thomas, not sure where you are in your project but in my opinion the place to concentrate is the heating envelope. Insulate well and build tight. If you can reduce the heating (cooling) requirements less costly options than geothermal might be your best option.

    I see geothermal as the technology for the rest of us. Those that built too big, with too little insulation, too many air leaks or all the above. Building science and materials of construction has evolved to make new construction far more energy efficient with reasonable returns on investment. I just finished a hydronic design for a modest sized home, about 2000 sqft, heat load at design (25F outside) at around 15,000 BTU/Hr. Back in the day, could easily be 3 or 4 times that. In fact with some builders, even today.

    If interested in researching what is possible (and practical), I have attached a link to the "Pretty Good House" as documented in Green Building Advisor as a good place to start. Basically good insulation, good windows and air sealing with Heat Recovery Ventilation. The common sense house. And you can follow the "Related Articles" in the link for further the discussion(s). https://www.greenbuildingadvisor.com/article/the-pretty-good-house

    All the best with your project. Jeff
     
  16. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    8 slinkies 600ft each 18" pitch, equals 9ft of pipe for 1ft pf trench, 65ft trench to each side, 3 ft wide, 10ft of center. 4800 ft pipe,

    33ft wide, 133 ft long
     
  17. Christian Ball

    Christian Ball New Member

    Hi Thomas,

    I was wondering if you could update us on your project.

    I am in almost the exact same position as you (new to new construction, new to geothermal, well and septic, and geographically... bloomfield township in michigan)

    Did you decide to move ahead with the geothermal?

    Thanks,
    Christian
     

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