Yes, I realize that there are MANY diff. types of furnaces, etc.
However I’m more interested in the brand. Basically furnace needs to be replaced in the next year or so (should’ve done it this year as it’s been so cold and could’ve saved myself some money)
Natural Gas. Current furnace is a Heil. Probably 1980’s. I’d LIKE to replace it with a 90% efficient furnace. The air conditioner coil and unit is about 7 years old (Trane 1500 I believe).
TOTAL sq footage in basement: approx. 750 sq feet
First Floor: approx: 850 sq feet
Send Floor (heated and cooled) square footage: approx. 700 sq feet
So I wonder, are say, Carrier’s better than Tranes, or Lennox? I do plan on having 3 contractors come over and spec something out, but given my last experience (when expanding the 2nd floor) I came to the conclusion that they just wanted to sell me the most expensive solution around. (I was told by the SAME company that installed the original air conditioner that “it’s not big enough for your house” and they wanted to sell me a 2-ton AC instead of the 1.5 that’s there already). They then tried to sell me a $3,000 heat pump.
–Kevin
Replies
Chose the contractor, accept his/her recommendation
_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
re - Chose the contractor, accept his/her recommendation
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With HVAC, I couldn't agree more.
Unless it's a Janitrol, then question your choice of contractor. <g>
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Barry E
Go ask these guys.
http://hvac-talk.com/vbb/
PS I like goodman-janitrol (g)
KK
Simple it is and isn't.
Don't take the dis on the Janitrol. It is one of the few furnace/ A/C manufactrurers that doesn't have the franchisee pitch to market. If you care ask. I own a Janitrol high efficiency unit that is sealed combustion. It is a thing of beauty & efficiency.
Selection of size. From what you offer no one (responsible) can tell you squat. There is a heating calculation required for all new construction. If your house is new or built near term there will be a heating calculation sheet with the inspectors office. If it is older than dirt then you have to do your own.
If you have to do your own calculation there are several heating calculation software programs on the web that cost upwards of 100 bucks. Some are Online friendly that allow you to fill it out but not run the real report unless you pay. Print a screen as you do it and you can get the result. If you are a pro then pay for the software as you'll use it more than once.
In essence you compute cubic feet in the house, windows surface with E ratings, insulation value in walls & ceilings, your "Zone ", (for temperature swings) and beyond that I can't remember what else. It is 2 pages of data that your original spec/posting doesn't begin to describe.
From all of the above stuff is computed the BTU values for your house. Heating AND cooling. That is the only answer that can be estimated and valued. All else is hot air.
NOW You also have experience from that you can tell yourself a lot. You have responsibility here to figure out what you need. Is the "X",000 BTU - 80 percent efficient furnace doing the job? is the 1.5 Ton Condenser doing the job? Only you know. Some of the performance is the balancing of the system season to season. Only you really know.
At 90% You are in mid-court in tennis buddy. 80 percent provides a vent and controlled exhaust without acidic condensation. 92% and above provide the acidic condensation line but they burn efficiently. No one makes a 90% unit. That 90% is a value theoretically where a furnace can't exist.
High efficiency has the PVC positive venting. In my opinion that is where you want to be (92%). In another opinion you ought to do the energy calculation just to learn whare your heating / cooling dollar goes. It helps you make rational decisions. Hit the web and surf for an evening to learn about the heating calculations, furnaces, and figure out your zone. You'll feel less detached from the experience. You need to know what people are doing for you. Otherwise you are making decisions on the look of the contractors truck, holes in their jeans, or the size of her tits. All pointless factors (sort of).
Good luck.
Here is a commerical calculator software that has a home version of $39. I forgot the details. But it is something like time limited to a few months or will only allow one project at a time.
http://www.hvac-calc.com/main.asp
Edited 3/16/2003 11:37:22 PM ET by Bill Hartmann
Good recomendation. At the time I did it (2 years ago ) there was no economy version and I think it was 300 for the cheapest package I could find.Jack of all trades and master of none - you got a problem with that?
Wow. Lots of detail, thank you. I shall have to play around with the software and see what I can come up with.
It appears that any NG furnace (forced air) that's 90% or higher "efficient" needs a separate input air vent for combustion? Can you use the existing 4" exhaust vent for EXHAUST?
Putting an input vent in may be a bit interesting (depending on how far it can travel feet wise) in my basement, given all the water pipes and where the natural gas meter and lines have been placed outside. But obviously that's my problem to deal with. hehe
--Kevin
Read the furnace manual and you'll get the info. Janitrol/Goodman have theirs on line. If I remember correctly it is an absurdly long inlet allowance.
Mine, 80KBTU is 4 inch inlet and outlet.
OH yes for those of us who don't like the white of the PVC outside the building, Krylon just took to market a paint that sticks to PVC. New this year.Jack of all trades and master of none - you got a problem with that?
It appears that any NG furnace (forced air) that's 90% or higher "efficient" needs a separate input air vent for combustion?
Optional for most, if not all, but be sure to follow combustion air supply requirements.
Can you use the existing 4" exhaust vent for EXHAUST?
NO ABSOLUTELY NOT! Follow the manufacturer's instrustions. _______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
For detailed HVAC help, try the following website - it was recomended to me by someone on this site 18 months ago, and I found it gave me more useful - and more detailed - information on HVAC issues than FHB:
http://www.heatinghelp.com/wall_forum.cfm
Good luck.
BTW - I've tried both FAG and hot water - and I'm now a complete convert to boilers / HWG over furnaces / FAG. Much more comfortable, even temperature - less dust and higher humidity as a result.Gavin Pitchford
Kevin,
I usually specifiy Heil products. I own their variable speed, two stage 94% furnace, and I highly recommend it.
If I understand your post correctly you have 2300 sf of heated and air conditioned space, 750 of which is in the basement. Without knowing the construction of your home or where you live, however, I would not speculate on the appropriate size you need. Where I live, 3 tons for 2300 sf is usually not too much, 2 tons would be a little "skinny" and 1.5 tons would be, in an average 2300 sf house, would be too small. A good contracto9r will run loads on your home to select the proper equipment. I would suggest that you replace ALL of the components as well as the furnace, to meet the the expanded house.
The reason I like Heil is because the support I recieve from the local reps is excellent. The quality of their products is comparable to Trane, or Carrier or Lennox, not particularly better.
"So I wonder, are say, Carrier's better than Tranes, or Lennox?" All manufacturers, with a few exceptions, are very competitive and offer very comparable products. The difference will mainly be in the supplier/installer. Compare products with identical or similar features, warrranties, etc., and see who gives the best responses (not necessarily prices).