seeking past experience in Norther Virginia

Discussion in 'Quotes and Proposals' started by huyle23, Feb 20, 2011.

  1. huyle23

    huyle23 New Member

    Hello everyone,

    I'm new to the site and I am seeking any information on past experiences with geothermal installs in Northern Virginia. Who did you use? Your experience with the installers? Any advice? etc.

    thank you
  2. huyle23

    huyle23 New Member

    some additional information

    My house is a new construction with around 3000 sq ft on the first and 2nd levels and 800 in the basement. R-15 on the outside walls and R-38 in the attic.

    Conventional heating (gas furnace for basement and main level and heat pump in the 2nd floor, vents, etc.) is already included in the cost of building. So I guess this is more like a retrofit.

    What's the going rate for a 6 ton system?

    How deep will I need to dig for a 6 ton system and what's the going rate for this?

    I know everything will be ball park estimates at this stage.

  3. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    your post title is specific enough that I didn't look the first time around.
    all I can suggest is that you look here and the igshpa website for local installers and ask them to show you something compelling.
    I'm not sure how you arrived at 6 tons but I am not convinced that it is a good fit for you.
    find local dealers, consult our shoppers check list and bring questions back.
    good luck,
  4. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    Virginia has fairly mild weather, I'd be surprised if the described house actually needs 6 tons.

    Do or get done a rigorous ACCA Manual J load (heat gain and heat loss) for your house.Since this is new construction, a room-by-room Man J will yield required airflow to each room - a standard to guide the HVAC contractor.

    Heating load may exceed cooling load by just a bit. Select system size halfway between the two (err toward smaller) and allow limited aux strip operation to make up the difference during the few bitter cold nights.
  5. huyle23

    huyle23 New Member

    Thank you

    Thanks for the replies.

    I sent my floorplans and specs to serveral companies and I'm waiting for their responses.

    I did get one back and this is their response:

    Loop - 160 ft/ton vertical earth loop. 960' Total Well Depth. Two (2) wells 480ft depth per well. Wells spaced minimum 20feet apart. 1.25" HDPE U-Bends in wells. Two (2) 1.5" diameter Supply and Return Headers ($18,000)

    Water Furnace Envision Model NDV 072 (nominal 6 tons), Variable Speed ECM Air Handler, Dual-Speed Copeland Scroll Geothermal Compressor. ($16,500)​

    Airside Ducted Zoning Controls, Three (3) Thermostats, and Automatic Aiside Dampers For Basement (Zone 1), First Floor (Zone 2), and Second Floor (Zone 3) ($6000)

    Duct System Installation and Duct System Design ($15,000)

    MERV 16 Media Air Filter Cabinet(s) for 5Ton unit ($700)

    Humidification Control: April Aire Power Auto Set Humidifier Model 700 ($690)

    1. Are they in the ball park with the well depth and loop requirements?
    2. Is $16500 a good/fair/bad deal for that model furnance?
    3. Is it typical to have 3 zones?

    I'll wait and see what other companies are offering.

    thanks again and any insights/information are greatly appreciated.​
  6. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    For $57 K I will be happy to drive all the way to Virginia to install your system.
  7. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Did they happen to share the heat lss calcs with you?
  8. geome

    geome Member Forum Leader

    Before a zoning/thermostat system is chosen, I would confirm that it has a lockout alert (and the installer will wire it), and confirm that it has methods of keeping aux heat from engaging when it is not necessary.
  9. huyle23

    huyle23 New Member

    docjenser, that's one of the disadvantages of NoVA. we have a good job situation as compared to the rest of the country but everything is more expensive.

    Joe, they did not share that information with me.

    geome, thanks for the information.

    second company said they'll have something to me next week. i think i'll have a better idea once it comes in.

    Thanks again everyone.
  10. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    I get northern VA as I visit often. Our daughter lives inside the beltway.

    I am with Doc, maybe we will both drive down.
  11. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    Perhaps I misinterpreted the square footage

    If there is 3000 SF on each of 1st and 2nd floors, then no, 6 tons isn't out of line

    $16k seems a bit pricey for that machine, but I'm hesitant to criticize contractors in high cost areas - they face unbelievable overheads.

    3 zones is quite reasonable for 3 floors. A challenge lies in having one very small zone (basement) A six ton machine makes 4 tons in low stage and that capacity requires at least 1200 CFM airflow. Stuffing all that air into an 800 SF basement zone could turn it into a wind tunnel. There are various strategies for dealing with tiny zones, I'd want to know what the contractor has in mind.

    $15k may or may not be pricey for ductwork - high for flex and ductboard, more reasonable for sheet metal.
  12. huyle23

    huyle23 New Member

    another bid

    We're going to sign the construction contact next week so it's getting close to crunch time.

    Thanks to everyone who've replied. I'm learning more with each post.

    Got another bid. They said that 6-ton is overcapacity and they're recommending 4 tons. I can go with a single 4-ton system with comfort zone 4 for $42k or two 2-ton systems for $46k.

    It surprised me that the difference between 2 seperate systems and 1 single unit is so small.

    My question is; are there any benefits between a larger single unit or 2 smaller seperate units? which one would you choose and why?
  13. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    In general with 2 heat pumps you can control 2 zones, can control a total of 4 stages, and you have redundancy. Usually one requires a larger system for heat downstairs, which is reversed in the summer, where the cooling load on the second floor is higher. 2 tons sounds small, especially for cooling a 3000 sqf second floor in VA. The advantage of using 1 pump with zoned ductwork is that one can put a larger capacity behind it if needed for 1 zone, but that can be a disadvantage too with too many zones, especially then the capacity might be too large.
    2 3Ton pumps would only be nominally more expensive, even with a 4 or 5 ton loopfield, and could provide more peak capacity, if indeed the capacity is too low. Best money you can (must!) spend right now is in a well done manual J, even if you are paying an outsider to do it.

    A "standard" up to code house with Richmond, Virginia, weather data should be fairly balanced total load for heating and cooling, around 62KBTU, with 5 tons having the lowest running costs. But it is about 46KBTU peak heating needed for downstairs, and 48 KBTU peak cooling needed for upstairs, assuming some generous windows facing south.
    Based on those "gestimates" over the internet, one could consider a 5 ton unit, with well sized ductwork and 2 zones for up- and downstairs, save a few thousand box with the 1 heatpump install, and an additional couple thousand box for 1 ton smaller loopfield.

    Disclaimer: This is based on quite some assumption over the internet! You need an accurate Manual J. Again, best money you can spend!
    Last edited: May 13, 2011
  14. huyle23

    huyle23 New Member


    Thanks for the detailed post.

    There was a miscommunication on my part. The house will be around 800 sq ft. in the basement, 1700 sq ft. on the main level, and 1700 sq ft. on the upper level. The basement will have 9' ceilings, 10' on the main level and 9' on the upper level.

    The rep I've been dealing with stated that they did a "room by room load calculation using Manual J8 – 8th version" based on the 3-page floor plan that I sent them. She did caveat the bid by saying a final calculation will be done once I supply the architectural blueprints from the architect.

    I've received 3 quotes using the same floor plans and 2 came back w/ 6-tons and 1 with 4-tons. I'm meeting with a 4th company in half an hour.
  15. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    That changes things. It is hard to imagine why a new build house with 1700 sqf on each floor in Virginia climate would be more than 50KBTU/h load, easily served by a 4 ton heatpump, with preferable 2 zones. What did they come up with in their "Manual J8- 8th version" heatloss?
  16. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    System size was first questioned in FEB. Load calcs asked about in MAR.
    They are yet to be provided........and the square footage of your house has changed.
    You should take all our advice with a grain of salt as we have so little data to base our opinions on.
  17. huyle23

    huyle23 New Member

    I'm going to take everyone's advice and pay for my own calculations. The companies did their own calcs as part of their bids but they wouldn't share that info with me. I'm assuming they don't want me to use those numbers to shop around or they expect others to do their own work, who knows.

    What confuses me is that all 3 companies have been in business for over 15 years (geo and non geothermal), IGSHPA certified, have a minimum of 30 installs. But they're coming back at 6, 6, and 4 tons proposals.

    These are the floorplans that I've sent to the companies.

    Attached Files:

  18. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Well, that house build to code in Northern Virginia with outdoor design temp of 10F (70F inside) has a heatloss of 46 kbtu/h (I calculated conservatively, it should actually be even less).
    In my neck of the woods, that is anywhere between a 3 and a 4 ton. In Northern Virginia, I would propose a 3 ton system to you.

    4 ton is justifiable, but not much more, 5 or 6 tons is not. Get you own heatloss done, and ask the companies for the manual J, and assure them confidentiality. You can confront them with the numbers.
  19. lcouch

    lcouch New Member

    Thoughts about some of your system and proposal questions


    I have two geothermal heat pumps in my home and am registered here as a regular user. However, in the interest of full disclosure, I will tell you I work for a Northern Virginia geothermal contractor, as well.

    I have a couple of thoughts I wanted to share with you after reading all the posts:

    • Performing a proper Manual J heat load calculation is a highly specialized and time-consuming effort that requires an investment in education, tools, and skilled professional resources. As with most services, you get what you pay for. If someone takes 20 minutes, uses only your plans, and does it for free, they're doing you a disservice. The load calculation takes into account more variables than what is included in a set of drawings (the 561 page manual is
    • here), and it should take hours, not minutes, to perform. We include Manual J's in our geothermal contracts, but we charge $999 to do them as a standalone project. For anyone who subsequently purchases a geothermal system, the Manual J fee would be subtracted. A Manual J calculation is a piece of design work that is required by most counties for new construction. You shouldn't treat it any differently than you would your (not for free!) architectural plans.
    • As for the pricing of two systems versus one, here's what's going on. The loop capacity will be the same, so the bulk of the outside drilling, boring, or trenching shouldn't be too much different. As for the inside work, the cost per ton decreases as the system since increases; e.g., two 2-ton systems are more expensive than one 4-ton system. Also, the labor to install any size system is about the same, so the inside portion (usually about half the total project cost) would be 2x if you're going to two systems. However, if you do the one system with zoning, you have to add the cost of zoning equipment and installation.
    • Keep in mind having two systems will increase your long term costs as you will want to have them properly maintained. I can't speak for everyone, but our maintenance prices are based on systems, not sizes, so the maintenance cost would b double. That being said, you do have the advantage of built in back up with two systems. If you have a system failure, you can still use the other one to heat or cool at least part of the house.
    • I'm assuming you're set on geo, but let me share with you my real results. I condition about 8,000 sq. ft. Once I switched to geo, my heating bills were all electric. This past winter, my largest electric bill was $250 (I'm not on budget billing).
    • If you didn't include a desuperheater option with your system, I would highly recommend one.
    • Even for conventional systems, the EPA has said that up to 30% of a system's efficiency is directly attributable to the quality of the installation. This is why you don't see HVAC equipment evaluated by Consumer Reports; the installation quality is that critical. So while it's tempting to look at the proposal price alone, you're going to pay more in the long run if you don't properly vet your contractor.
    • I tell everyone who buys a system to keep copies of their utility bills. While you're starting out with geo rather than converting, it will still help potential future buyers and hopefully even appraisers to see the actual data.
    While everyone tends to focus on the energy savings, I can tell you that I love my geo system for so many more reasons; the 'green' makes me feel good, I don't have outdoor units I have to hide or trim around, the outdoor units aren't making noise while I'm trying to relax on my deck or by my pool, and my indoor units are much more quiet. Hope you enjoy yours, too!
  20. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    "Performing a proper Manual J heat load calculation is a highly specialized and time-consuming effort that requires an investment in education, tools, and skilled professional resources. As with most services, you get what you pay for. If someone takes 20 minutes, uses only your plans, and does it for free, they're doing you a disservice. The load calculation takes into account more variables than what is included in a set of drawings"

    "Highly specialized?"
    I think you are exagerating this a bit. While some knowledge is handy, with modern software and a brain most can do a load calc in a short period of time and with a simple home 20 minutes is not out of the question.
    $999 dollars on the other hand is a bit much. If you get it more power to ya.

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