Trying to Decide on the Best Geothermal System - Can you help?
We have been reading your website for weeks. We have gotten many quotes. Now it is time to make some decisions and we still don't know what to do.
We currently have a 30 year old outside compressor and a 20 year old oil furnace. The compressor died and we will be replacing with a closed loop geothermal heat pump. The federal, state & county tax credits & grants bring the final cost very close to a conventional system. We are excited about that but want to be sure that we are getting the right system.
We just north of DC and have a 30 year old 4500 sq' home (including finished basement) with a 4 ton compressor. The upstairs never gets hot or cool enough. We have had 6 quotes - some say only a 4 ton is acceptable (because that's what we have now) and others say a 5 ton is best as long as we have a variable stage blower (which we do want). One measured our ductwork and said it is of sufficient size to accommodate a 5 ton. So, that's the first question - what size should we get.
Second question - which brand to purchase. We have quotes for Bryant (most expensive), Water Furnace Envision, Climate Master Tranquility 27, and FHP/Bosch.
Third question - which company to go with. We have 3 large companies that have done hundreds of residential and commercial (these are the most expensive); one large co. that is trying to break into residential geothermal and has done 100 commercial units but only a 4 residential; and our favorite HVAC guy (whom we have used for 20 years) who has installed many HVAC systems but only 3 geothermal (and these were all open loop) and is only authorized to sell one brand.
And fourth (I know - I have so many questions, which is why our heads are spinning) are all the options. Do we get the Honeywell true steam or another brand of humidifier (we will be running the system on low full time) and do we pay for an enhanced filter system or just use the 2" filter they provide? Do we get the ultroviolet mold reduction light?
If anyone could help on even one of these issues, it sure would be helpful. I'm thankful for all the options (I've heard some areas of the country can't even get multiple quotes) but it sure is making things confusing. Thanks in advance.
First I would say that I am not a pro. just a home owner.I have a waterfurnace and it has been great, no trouble at all, but if it is not put in right it will not work, there is little room for mistakes. Get a very good installer and watch eyerything he does. I found some mistakes on my job that would have cost me if I had not been watching. ie Two systems with no check valve on the same well. shipping bolts left in both compressors, and no antifreese put in water with 1 foot of line exposed as the lines leave the house in the back yard. Grout was put in from top down not bottom up. I think if you are going to expect something you must be willing to inspect. I know that a lot of people think that you shouldn't have to do this. If you read many post you will see alot of people that wish they had. I want to be positive Geo is one of the best things I have ever done and I didn't get the tax rebate you can't go wrong.
I can only give you my experience because I'm also just a homeowner, but I have a fhp unit that has never given me problems. I think the important thing is to make sure whoever installs the system shows you heat loss and heat gain calculations to prove they are installing the correct size unit. Then you also have to do a sanity check on your loop size and design to know if it's reasonably sized for the unit.
In my opinion, the guy who said he wanted to install a 4 ton because that's what you had before should be off the table immediately. My gut tells me a 5 ton makes more sense especially if you get a 2-stage compressor. Just make sure they install plenty of loop, and prove to you that your flowrate is within spec. Generally they recommend 3 gpm per ton for closed loop and half that for open loop.
It all depends on your heat load of your house - my 4500 sf house is super insulated located in northern Louisiana with a Climatemaster 4 ton geo unit and it has no problem even in 100 degree afternoons. I have 6" walls (r20) and r50 in the ceiling with the best double pane windows I could buy. My full basement is always cooler than the upstairs but that is life. I set my temp at 78 deg f for the upstairs temp.
How about the "extras"
Thanks for sharing your experiences. I think we have finally decided to go with one of the two contractors who have done hundreds - their price is comparable, but one company has also offered to get our current system up and running in the meantime so we don't have to go through the 100 degree/90% humidity month of August without it. Very tempting.
Cdhand -- it is almost unbelievable that this many things went wrong in your install. You are correct, it sure did pay for you to oversee that process. You bet I'll be there for mine. Thanks.
Crash11 -- all of the quotes say that they will give me the official heat and load calculations after I select them (except the one who was sure of the 4 ton). I'm actually contracting with my own well digger (from their approved list) so the size of the loops will be in accordance with the equipment requirements. I'm glad you had good experience with FHP. I do think I am going to end up going with Water Furnace, though, because that is the company we can find the most positive comments about and that is the brand the most experienced installers around here are using. My husband has pretty much made up his mind on that one factor last night.
Quailtrail -- That's awesome! I wish our house was that efficient, but I don't think it is. But, I'll rely on the load calculations they come up with at the end.
What have any of you done for your "extras" - this is our other big sticking point. The filter (do we go 4-5" or stick with the 2" that comes with the unit) and humidifier (we definitely need one - truesteam or Aprilair) mostly. I think we decided against the ultroviolet light because the coating on the new waterfurnace won't allow for this.
You need the heat gain/loss cals BEFORE you sign with a contractor. The size of the geo is directly related to those calculations.
As far as the extras go, I didn't get any. I put a humitifier under my return air in the basement and that has worked fine for me. The two inch filter is all you need, it is much better than you have now, I would think. They are very expensive,you can save half price if you are willing to buy 12 to 24 online. I would want my contractor to get the well digger so that if something goes wrong he can't say that problem is not my fault, it is the well diggers, my hands are clean, the warranty will not cover this. All of my problems other than the shipping bolts were the well diggers fault. This is BIG THINK TWICE about it. Good luck and if I can help my email is email@example.com
The heat loss/gain load calculation is very important and the loop is designed around those numbers....so make sure the loop is sized properly.
If the upstairs did not heat and cool properly before hand (red flag) Geothermal will not fix that without duct and/or insulation modifications. GSHP's require more air flow than a conventional furnace and that means larger ducts and/or more of them. A variable speed fan motor will not make the problem go away and it could turn your ductwork into a giant whistle.
The 2 biggest problems with geothermal installations relate to duct and loop issues and there is no easy fix for either down the road.
The best brand to buy is the one that is sized and installed properly by a competent geothermal installer.
Bergy - Thanks - I will have them do this before signing.
Cdhand - Thanks for the "extras" help. All but one if the contractors here required that I sign separately with the well digger. They simply "approve" them. I wonder if that is a regional practice. This digger has done a thousand plus over the past 20 years (including many commercial) and did over a dozen this past month alone.
Teeball57 - Thanks for that heads up. We just bought our house in December so I'm not sure if the refrigerant was low or if there were other problems. We have also been considering adding an attic fan as we have something called a mansered roof (sotr of like pizza hut) with not much of an attic.
Consider paying for a Manual J and D analysis independent of bidding contractors. I do them for $300 for a typical house, and the reports (whole house load, individual room airflow needed, individual room measured airflow) become the intellectual property of the homeowner. They can choose me to make improvements or use the reports to engage another contractor.
Watercop - Well, your advice is great but a little late as I already signed with a contractor. They sent someone out to do a load analysis before I signed and we found out the requirement and the big problem. The requirement is for a 4.7 ton so we are going to have to go with a 5 ton. The problem is that a supply duct runs through our tiny little attic (the style roof that pizza hut has - I think it's called a mansered roof). The supply duct is not insulated and the attic is not vented. Now on to the fun part ... getting that taken care of - either with ridge venting or some sort of fan system. On to more research for us...
Hi A Maryland Mom, I am new to this and the geothermal, and very interested in getting started, could you, and am in Rockville MD. Could you tell me more about what system you have and whom you hired, and how do you like your new system? Thanks
I do not think that it makes much of a difference as long as they come from a well know maker. There are several major manufactures and they all operate with the same technology and use the same physical principles.
Originally Posted by violiu
The most important issue is the loop design and placement. That is where the money are and that is the most important and critical part of the future system.