You can hire an IGSHPA accredited installer for your residential project. A Certified GeoExchange Designer is required for commercial, industrial or institutional projects. However, the Certified GeoExchange Designer could also be hired for residential projects as well but probably at a greater cost since they are usually professional engineers.

SR

STOP! And how much did the HVAC contractor do ...to give U a heat load and cooling calculation? Did U get a blower door test? A duct leakage test? Has upgrading insulation levels or possible replacement energy windows FIRST! There by giving U a
pre audit of investment dollars, vs, just installing to Old 1958 insulation standards and window standards. Ranch homes
that are semi-daylighted often have little cooling load but the heating loads can be much greater. There R a lot of buz words in this market today...

Why would U do a heat/cooling load if U knowing these systems can cost 6, 7 grand per ton installed...knowing U want to investigate the possibility of LOWERING the actual
tonnage first and project your savings and reduce the size of your equipment on the front end of a project. Anyway if U need help email.

Hi Chuckfh,

Yes, to all of your questions. I have replaced all the windows and doors with double paned, low-E glass, argon filled vinyl windows. I replaced the roof with a 30 year architectural TAMCO roof. I installed 18" of additional insulation, blown fiberglass and rolled. I had a blower door test and an energy house inspection by TerraLogos (www.terralogos.com) which prompted me to consider a Geothermal system. My current AC system is on its last legs. I have two 4 ton units (probably overkill) and was quoted about 20k to replace these and the condensers. Since I have uneven hot and cold areas in my house it made since try to consolidate the three systems (2 AC/ 1 heat) into one modernized system. The big unknown at this point is if any of the three existing duct work systems are usable with the new GSHP system.

The load calculation was done by a reputable HVAC firm and they did a manual J using 2008 software to model my home.

The blower door test did show significant air leakage (mainly through AC ducts and original wood paneling). So if anyone knows a contractor who specializes in air sealing please let me know. I'm in Howard County, MD. I'm thinking there has to be a way to remove just the lower portion of the siding (wood board and batten) and seal the band joist. I've already done a ton of chalking and some foam spraying based on the BD test results.

Thanks,
Deb

Hi Deb,

I got a surprise...later down in the posting!
Sound like you are heading in the right direction. Can I assume, the third system, we will call it the boiler system is serving all of the rooms? And the other two air systems, we will call them cooling zones 1 and 2 serves all of the rooms also? Where are the Air handling systems located?

Did each of the 3 air systems get a separate leakage test with a duct blaster? Or did the auditor only use a Door Blower and give you relative duct leakage information? Do you know the whole house infiltration rate? Can be found on the auditor report. Something like: ACH [Air Changes/Hour] And can I assume the HVAC cooling/load test was done afterward? Is your home two stories with a basement? Go back to that www.terralogos.com company. I would be shock if they dont directly perform this work or they donÂt have someone that does it? Now here is the surprise

I would not have any ductwork sealed yet! Till more information is gather. Today they seal ductwork from the insideÂlike flat tire sprays. I found one of these companies on a website from Fredrick. I called them too see
if their telephone number was correct and to ash a few questions about their service cost etc.

I called them, spoke to John, and I was asking about this lady in Howard County, asking if they service Howard County. One thing lead to another trying to get a general price so I could post it here for you I told him it had two 4 ton a/c units and is thinking about doing Geo Thermal, he ask me if it was Debra ______, I told him it may be and you were a friend. HeÂs been to your home with advice, they where refered to you via Terralogos? This is a small world. Of course John is recommending not to install Geo Thermal and wanting to replace one of the systems and add zoning.

What ever U do. Merging two systems into One, maybe able to be done and zone the two floor and 1st floor will smooth out
the comfort issue. However, from listing to John, I do concur with his appraisal of the duct systems in your home.

Good Luck
Chuck Halloran
Steel Skeleton, Inc.
Chattanooga, TN

ps: It sounds to me John has a passion for doing things right, They are a fully licensed mechanical contractor co. doing lots of HVAC work beside duct sealing. I told him, I'll let Deb know we talked. He believes, I am a friend of a friend of yours and she was inquiring into some question about hvac questions and I was just trying to help her. The Internet was never mentioned.

Hi Chuck,

Yes, it is a small world! It's really funny I've had TWO previous coincidences or "it's a small world" moments since I started on this geothermal quest. Both of these were related to HVAC contractors who know each other, either through a personal friend of mine or as business acquaintances.

Anyway, it seems my house has a unique (challenging) setup in terms of the duct systems. You are correct in all your assumptions. The AC (2 zones) has 2 condensers which are located in a very low pitched attic while the oil boiler and heating air handler are located in the basement. The house has two stories built into a hill so the basement has 8' ceilings and is above ground on the rear and left side of the house but the front and right side are underground.

Your questions regarding the testing of the systems make a great deal of sense. It sounds like I should have a duct blaster test. Here is what I know - (1) I had a blower door test which I think measured whole house leakage and the ACH in the house was high, .81 ACH; (2) No duct blaster was used but one of my geothermal contractors who wants to bid on the job wants me to spend over 2K upfront to have each duct system tested ($680 per system) "to determine the amount of airflow each register is receiving, which main line each register is coming off of, and other pertinent information needed to make a conscientious decision;" (3) Thermal heat images showed major air leakage in one of the AC duct systems. The returns for that system were like black holes in the photos; (4) The heating/cooling load calculation was done after the home energy audit.

John, from Frederick Air is WONDERFUL, very dedicated, experienced, knowledgeable, etc. I would have him do the work and said as much but as you know his company doesn't service Howard County! I had John come out to see if that one leaky AC system would benefit from sealing it using Aeroseal.

The big unknown seems to be whether it is more costly to seal and/or modify the existing duct systems or alternately tear out the ceilings and some walls (in my newly dry walled basement!) and install new ducting for at least the main line.

It's interesting that the cost of replacing the systems and zoning is almost as expensive as switching to geothermal. One contractor is re-evaluating the duct work today with his "duct specialist" and I'm meeting another geothermal contractor on Tuesday next week. Then next Friday I'm meeting with the contractor John recommended who specializes in multiple zoned HVAC systems. However, if you take into account the state and county rebates offered for switching to geothermal, I think it will actually become the more economical choice.

I'll ask TerraLogos about the duct blaster test. Should I have that test done? The thing is, I'm not sure if the cost of all this testing is worthwhile...basically I've paid a small fortune to verify what I already knew - my house has uneven airflow and distribution as well as leakage...

At this point, my gut feeling is that the existing duct systems should be scrapped (metal recycled of course). That way, the winning contractor can start with a clean slate and build a retrofitted, truly energy efficient system.

Thanks so much for all your input! Let me know if you have any other thoughts.

Deborah