Good day
I am building a home this winter and am considering geo if I can justify the costs.  I was wondering if there was someone on this forum who has the programming and knowledge to properly size the machinery I will need based on my build.  I would like a totally independant take on this so that when I get a quote from the installers I know they are not trying to rip me off, or have done the calculations right.  The reason i am looking for an independant take is because of the people who i have talked to here, I am getting such a variance on machine sizing on prelim discussions that even when i get the quotes back, how will i know who has sized it proprely?.  If i had one or two independent assessments that came out close, maybe I could weed out the ones who are way different.  Or does anyone know how i can do one myself for free and easily that I can figure out how to input myself.  Any other advice on geo will be appreciated as well,
regards nathan

For $50 you can download Don Sleeth's normally $389 (last I checked) HVAC Calc and do your own calc. $50 buys a 60 day license. I have a single data point supporting HVAC Calc's accuracy - it was quite close to the result from $500 EliteSoft load calc software, and proved correct for my own home.

If you go to the trouble of insuring good inputs to the software you will learn a bit. You can play with various building material and detail choices and assess their impact on the structure's load. I especially recommend doing this since you are about to build - you are in the driver's seat. In addition, if you decide not to go geo, the load calc is still valid - works for any system.

HVAC calc is what I would use if you hired me to bid your job.
j

Another option is to solicit local contractors to do a load calc for you for pay, with the understanding that the payment would be credited toward the cost of your system if you select that contractor. Any good contractor can and will do a load calculation in the course of system design, but may be reluctant to supply one for free to a potentially unscrupulous homeowner or builder who then shops the design calculations to a low-bidding hack.

thanks I will look into the hvac calc, and I will be having several local companies quote the job, but I was looking for an outside independant source that  could do the calcs as well just to run them against local contractors to see who is doing them right and who is not.  The reason i am doing this is because everyone i talk to has a different opinion about the geo companies and even some of the installers i have talked to have such a difference in what I will need based on prelim discussions that I cant tell who is doing the calcs right or not.  for instance The other day I was told by a larger more known plumbing company that has been in opreation for years that they would only recommend one company for any geo work, and it is a company i had heard of. the next day that same geo company was being slagged off on a public website by an irate customer.  Then today I went to get quotes from two diff companies and submit my plans and told them what I was doing 1800 sq ft bungalow, no walkout, ICF to the rafters, solar ban windows, possibly solar panels, r 40 and maybe more in the roof and i was told by one guy based on initial discussion i would need at least a 6 tonne machine and then the next guy told me probably close to a 3ton unit. so why the huge diff, how do i know who is doing it right.  the only thing i can go off of is that i know that by using icf to the rafters i should be able to dowsize my mechanical installations even if I am not using geothermal, so makes me believe the guy selling me a six ton unit is a hack and after my money, thus the reason for some way to do an outside independant calculation that i will have no ties with and aren;t just trying to get my money.

Well you didn't provide your location, but my guess would be a 3 ton is probably a 100% design, a 2 ton might work for that house (if your climate is similar to mid MI). Do the one time load license mentioned. Give us your location and heat loss and we can help from there. Don't share the loss calc with bidders, let them "own" their numbers and design.
6 ton guy probably doesn't know geo and will cost you in installation, duct work and operation (unless you are in the Arctic circle).
joe

I am in saskatoon, saskatchewan, so pretty cold but not the artic, what do you need for the heat loss, is that what the program will tell me.

Since you are in Canada, HVAC Calc is the wrong program to use as it is referenced to Manual J, an American standard (ACCA). You need something like 'Wrightsoft', which can be refenenced to the Canadian HRAI Can/CSA F280 M90 standard. The Canadaian heat loss/gain standard is essential if you expect to recieve any Federal grants.

Hire a contractor that has been accredited by the CGC.

SR

I was unaware of a different Canadian standard - good catch. However, Wrightsoft may not be geared toward one time use by homeowner - too expensive. HVAC Calc should still work to validate local bidders. My Elitesoft suggests winter design temp of -26 for Saskatoon, a bit colder than MI, but I second Joe's remark that 6 tons is way off given the construction details you describe.

One of us here would probably take a few bucks from you and spend the hour or two needed to key in your design and produce design loads. The design work doesn't end there, though - there are exterior considerations - the loop field and its entering water temperature as well as the interior duct system.

Give serious thought to sprayfoam insulation such that the attic wherein all the ducts live is within the conditioned envelope - makes a huge difference.