Help Selecting a System

[hstead]

I am a homeowner currently building a new home. I have contacted several HVAC contractors and I am getting many different opinions and options. I am seeking advise from the pro's on which system I should go with. My home is as follows:
underground basement 1600 sq ft.
First floor 2100 sq ft.
Second florr 1600 sq ft.
garage 1800 sq ft.

2X6 framing located in Southern Ohio

My options are :

Water Furnace Geo Thermal 31 seer 5 ton down - 3 ton up
Trane Geo 25 seer - 5 ton up and 5 ton down
Waterfurnace 31 seer 5 ton down - american standard 3 ton up
Trane Geo 5 ton down and trane 13 seer heat pump up
Trane 13 seer heat pumps 5 ton up and 5 ton down
American Standard 14 seer heat pumps - 5 ton down 3 ton up

I have one contractor telling me I need 10 total tons, one telling me I only need 8 total tons, and one telling me I need 9 tons.

I am confused and do not know which system would be best.

Thanks in advance with for your help.


[Edited by hstead on 12-21-2006 at 12:13 PM]

[ambarton]

ask these guys to show you a load calculation to see where they came up with their numbers for tonnage. this should weed out the wanna'bees and get you the pros. if your sold on a geo, get refrences where they have installed in the past. i cant imagine any homeowner who is satisfied with their system not giveing a good referral. a poorly installed geo system can be more of a headache than a brain tumor. just my opinion

[hstead]

One contractor has calculated 5 tons down and 3 tons up based on the number of ducts he said. He had a rule of thumb, something like four ducts per ton.

The second contractor calculated 5 tons up and 5 tons down saying that I needed 5 tons up because the run to the garage, which needs two ducts, was so long that I needed a larger fan and larger unit to make that long run.

As for Geo, I am not sold yet on how much I would save versus heat pumps or even lp gas furnaces and AC's.

[dash]

If the upstairs is equal in sq. ft. to the downstairs,it normally needs more cooling then downstairs,as it has an attic and the downstairs does not.

Ducts to the garage just need to be sized correctly,due to the extra length,now space to run them needs to be available.

Bottomline;
Find a contractor that can and will do a Manual J,S and D,to size the equipment,select the equipment and design the duct system.These are the indusry and ANSI standards,created by wwww.acca.org

[davefr]

Originally posted by hstead
One contractor has calculated 5 tons down and 3 tons up based on the number of ducts he said. He had a rule of thumb, something like four ducts per ton.

The second contractor calculated 5 tons up and 5 tons down saying that I needed 5 tons up because the run to the garage, which needs two ducts, was so long that I needed a larger fan and larger unit to make that long run.

As for Geo, I am not sold yet on how much I would save versus heat pumps or even lp gas furnaces and AC's.



>5000 sq ft and HVAC systems well into the five figure range and they're using "rules of thumb".

Send the first contractor packing!!

If there was ever a case for a detailed Manual J then you're situation warrants it.

P.S. The moderator will spank you for quoting pricing. You might want to edit it out before you get caught.

[wyounger]

Propane will eat you alive, though, trying to heat that much space in a cold climate. If you're going to have it around for a stove and/or fireplace, fine. But the cost of heating a place like that with propane furnaces is just a non-starter.

Heat pumps are more reasonable up front but will cost more to run.

Geothermal is very expensive up front but far cheaper to run... I'd expect to use a little less than half the energy with a geothermal system than with an (air-source) heat pump.

There aren't so many people that really know what they're doing when it comes to installing and servicing geothermal systems. If you are going to take the leap, be absolutely certain to talk to clients who have bought geothermal systems from the contractors you're considering. It's too much money to risk getting an improperly specified, designed, or installed system; that's just bound to turn into a very expensive lemon. You're not just buying a factory-made machine with a compressor in it, you're paying for them to site-build these water loops to exchange the heat with the ground. If the loops leak, or are too small, or are too restrictive, it doesn't matter how good the factory-built equipment is. I say the same sorts of things about traditional equipment, though; a huge part of what you're buying is the labor and expertise it takes to match the equipment to the application and install it so that it can perform as the factory designed. Sadly enough a lot of what goes on in this industry is driven by brand names, price pressure, rules of thumb, and installation work that might be good enough to make the system run but isn't even close to proper.

[hstead]

Thanks for the advice fellas. I have asked one contractor to give me a Manual J, which he is going to do. I think that will help me tremendously towards how much I need on each level.

Now I need to decide on conventional heat pumps or Geo.

Hoe much of a difference is there between Water Furnace, Climate Master, and Trane's Geo?

[johnnyde]

The thing with geo thermal is, it has to be be done right. There is alot of engineering involed. For instance the contractor needs to know what type of soil the loops are being installed in, the average temp in summer and winter for your region. How deep the wells or loops need to be based on tonnage, and what size the lines need to be. Bentanite will also need to be sprayed in the loop or well. If any of these things are not done right or half assed you will have problems, and the won't go away. I would do alot of homework. The more you know the better off you will be.
The difference between the three brands.
TRANE- I have seen alot of compressor failures.
CLIMATEMASTER AND WATERFURNACE- They are both about the same, as far reliability.
Trane and Climatemaster you will need extra room in front of the units for maintenance and service. They have a stupid design on the control panel. It's a drawer that slides out, so dont box the unit in if you finish off the basement. If possible I would leave as much room around the unit as possible.The bottom portion of units have access doors all around it which helps for service.Good luck.

[beenthere]

Since when is the garage allowed to be on the same forced air system that conditions the occupied area.

[BaldLoonie]

Being next door to you we have similar weather and I would guess similar construction methods.

8 tons for 3700 sq ft (basement is minimal and garage doesn't count) seems very excessive. 2100 sq ft first floor with upstairs above most of it sure shouldn't need 5 tons unless you are all glass! Be interesting to see what the manual J calls for.

Instead of dropping a bundle on geo, have you considered putting it into foam insuation so you use so much less conditioning inside?

[pstu]

Baldloonie put into words something I was wondering. Except he knows the region and climate and is a pro, while I am a homeowner in S.Texas. Anything approaching 370 sqft/ton sounds like old school, huge oversizing! Usually that would be excessive in Texas, I was wondering if the heating load had a super large BTU need. Sounds like you will be constantly pushing with this project to get it done the right size, the right way. Insisting on Manual J is an excellent step, as a cynic I have to wonder if they are actively trying to fudge the numbers higher to be more comfortable with old school.

You in the "North" have a real advantage, it is cheaper and easier to get energy efficiency, including passive solar design. By the latter I am thinking at least lot orientation and window choice. In addition there are a lot of fine schools and fine engineering minds which are in the Northeast, you get a lot of brain power working on the cold weather situation. It is no coincidence that Amory Lovins with his Rocky Mountain Institute, zillion dollar practically no energy home, is located in the Rocky Mountains. By contrast we have a smaller number of people working on problems of the hot-humid South.

I sure hope you go over those tonnage numbers with a fine tooth comb, the result for my 1989 vintage house, pretty good construction but not great and lots of windows, is approximately 700 sqft/ton according to Manual J. Our climate is so different though, listen to the pros like Baldloonie!

Best of luck -- Pstu

[t527ed]

Since when is the garage allowed to be on the same forced air system that conditions the occupied area.



that can't be legal ANYWHERE !!

[hstead]

Thanks again guys.

I have thought about sprayed in insulation. That is my plan, however, in southern Ohio we do not have many "pro's" and my contractor is having a hard time finding a blow in specialist.

I have decided on heat pumps now versus geo due to the cost. I am not convinced that I would get my money back with the performance of the new air-to-air heat pumps that I am reading about.

I have picked a HVAC contractor on the contingency that he gets a Manual J completed and we go with that.

Now I am trying to decide between a two-stage 16 SEER and a single stage 14 SEER. He can install American Standard or Trane, but the AS is slightly less expensive. I understand they are basically the same units with a different name on the outside.

I should clarify, the down stairs is 52X40, roughly 2100 sq ft. And the upstairs is the same size however the downstairs family room has a vaulted ceiling, leaving the actually floor sq footage at 1600 upstairs. I was not planning on ducts in the vaulted ceiling.

Thanks again for the help. This site has really helped me make these choices. It is noce to have access to pro opinions.

[dash]

Thanks for the advice fellas. I have asked one contractor to give me a Manual J, which he is going to do. I think that will help me tremendously towards how much I need on each level.

Now I need to decide on conventional heat pumps or Geo.

Hoe much of a difference is there between Water Furnace, Climate Master, and Trane's Geo?

Manual J without S and D will not insure the corect size ,effiency,or comfort.

All the manuals are from www.acca.org they are the ANSI and industry standard,get someone who will do all three.