Buying new furnace & AC - questions

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Hi everyone - my apologies in advance for the long-ass post:
The time has come to replace the 25 year old furnace in my recently purchased house. I'm planning on also replacing the central air while I'm at it. While I'm not thrilled about having to put out the dough, I am looking forward to resolving my biggest peeve with my current system - which is that the air conditioning has trouble getting to the upstairs of the house in the summer.
My house is tiny - about 1,200 square feet. It's a Cape Cod - officially it's 1.5 stories, meaning that the upstairs bedrooms are actually in the attic, so to speak.
I have 2 quotes that I'm dealing with. The first vendor wants to install a Trane furnace (2 stage, 92% efficient - 80,000 BTUs) and a Trane AC unit (I think it's 14 SEER). He noted that I have asbestos in my basement, which butts up against the "main" ductwork (sorry, don't know the correct terminology); he said that the existing ductwork was fine and that I wouldn't need to have the asbestos removed. He said that my cooling problem might be the result of having the wrong sized AC unit installed; he also suggested that I raise the registers in the upstairs bedrooms to the middle of the wall (about 3 feet up - they are currently down around the baseboards) to help spread the air around.
Vendor #2 wants to install a Bryant 80% efficient 2-stage furnace (70,000 BTUs) and a Bryant Puron Plus AC unit (13.5 seer - upgradable to 14.5 for some extra $$$). He said that my cooling problem is probably due mostly to improper air flow, and that I'd need to have the asbestos removed so that he could make the return air trunk line larger.
The Bryant guy's quote is almost exactly $1,000 less than the Trane guy's quote, but having the asbestos removed will even that out. Anyhow, my questions are many - I know that they're difficult to answer without actually seeing the situation, but here they are:
- Could there be any equipment differences between the Trane and Bryant brands that would explain the vendors' difference of opinion on the size of the return air trunk line?
- Any opinions on Trane vs. Bryant?
- The Bryant guy wants to charge an extra $250 to install a Honeywell T8600 programmable thermostat. I can buy that same model on the web for $106. Is there any great skill/advantage to having the contractor install it? For $250, I could buy the thermostat and have my handyman buddy install it - *and* wallpaper my bathroom after he's done.
Any other opinions, advice, etc. will be greatly appreciated. I really would prefer to install the Trane - the warranty is better, and it's just better looking, darnit - but the whole airflow argument concerns me, and I don't want to put out a bunch of money for a new furnace/AC if its performance is going to be hampered by inadequate ductwork.
Thanks much! - Ali
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Unless you live where your heat bill is mimimal like Fla get a 90%+ unit, my Ng is up 60%.
Did either guy do a load calc or ductwork calculation in writing, Guy # 1 sounds like a real hack and is larger in btu on a more efficient unit, not good. You don.t want to oversize, ask to see the written load calculations they performed to come to their conclusions on sizing of unit and ductwork, I bet you wont, so get someone that will do them.
Poor second floor cooling , is a return upstairs, you need a real pro not a guy that says to just raise registers and that " your AC Might be the wrong size". There is no guessing for a real pro, they use math and formulas.
Asbestos we cant see it but often best is leaving it and sealing it in place, encapsulating it, so it cant be knocked loose, taking it off is costly and Will spread it around.
Check out what other manufacturers offer and even all the options of the companies you are looking at, today there are more optiions then ever that make for a more comfortable home and greater efficiency than what you have been shown. Go online.
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m Ransley wrote:

Hi, I am in Alberta. When NG price goes above 8.50 per Giga Joule, provincial government provides cushion above that in the form of rebate on our NG bill. Throughout heating season the program costs about 800 mil. Your country can invade a sovereign nation at a great monetary/human cost but no such program for people struggling with basic needs? Every one in Alberta gets 400.00 check in the mail new year comes. Government is swimming in black ink. Tony
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Tony Hwang wrote:

Bush used up all our black ink and then some.
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CJT wrote:

This is Turtle.
i wonder if any of the Congressman or the house Of Rep. voted on the giving away all the black ink or did King Bush just give it out without them knowing about it .
TURTLE
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TURTLE wrote:

I guess I should have said Bush and his fellow Republicans.
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PRESIDENT BUSH DOESN'T CARE ABOUT BLACK INK!!!
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Tony Hwang wrote:

If your meal at a restaruant exceeds 2,000 calories, does the government step in and pay the difference?
Why should the US help someone struggling with "basic needs" in Alberta? Your provincial government has a monopoly on that area. If you're talking about "basic needs" in the US, we do. It's called Florida.
And in the pot/kettle mechanism, Canada invaded a soverign nation, at a cost of 1000 lives in nine hours. August 19, 1942. Canada tried again two years later, with even greater loss of life.
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Yes get a Guarntee of performace in writing as Bubba said, I forgot about this, when my folks had Spacepack installed they had a Written Guarntee of 30f drop and when it reached 115 it was 75 inside. It truely is the installer who makes it work. We had other hacks bid who wanted to run ducting on the floor of the attic or put in 2 bigger units , So truely it was The installer that did the pro job and made it work and us happy. In my home my installer told me when retrofitting AC " You need a return on the second floor or it wont cool" So one was put in and it works. You have probably 2 hack bids, it all has to be calculated by industry accepted Load calculations called manual J and D? I think those are the designations. Of all the bids Ive recently got on a furnace Ive had to finally demand a load calc from the installer I liked, and to his suprise he found he oversized his original assumption, since I have done things like insulate basement even under concrete and R 100 attic. Don`t do anything till you see and get a copy of the written load calculations and temp drop or house temp in writing .
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Why save 100 $ on an unwarranted thermostat, or one you could ruin or have not work by improper install.
Carrier- Bryant, Lennox, and others have thermostats that have outside sensors, fan run speed, humidifier controls, Low Speed humidity removal modes in AC " which with VS DC pull double the moisture out, good on 72f days", etc etc, more than you want to hook up or know how to do right. Put the wrong wire on or with power on and things can fry.
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There always has to be at least one ass ready to turn a question about a new furnace into a political attack. For your information Tony, the US has plenty of programs to provide heat, food and shelter to those unable to provide it for themselves. We tend not to like folks like you though, who expect welfare checks to come in the mail from a socialist government for everyone. The money the govt sends out has to come from somewhere, but then you probably don't have a job so you don't care about paying for socialist programs with taxes.
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m Ransley wrote:

I have to agree with all of the above and emphasis a few things.
The most important part of your choice is not what unit to buy or what manufacturer, but what installer is going to do the job.
That job includes doing the proper calculations to determine what size equipment you need, not just a quick look around and considering floor space.
No matter how cheap your NG is now, it is very likely to be much more in 25 years so I suggest throwing out that bid for a 80% unit.
The cost of the new thermostat may include additional or replacement wiring to it if the new equipment needs it. You may or may not be able to do that yourself depending on your skills and the complexity of your specific situation.
--
Joseph Meehan

Dia duit
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Did either take any measurements, ask about what kind of insulation is in the walls or do anything other than look at the model plates of the existing units, walk through the place, and listen to you say it doesn't cool enough upstairs? Seems to me there ought to be at least a little science involved.
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No, there's no advantage to having the contractor install your thermostat. If you have a screwdriver you can install it yourself. If you're not that confident, then get your handyman friend to do it. It'll take all of 15 minutes.
Mike
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wrote:

Simple. Your cooling problem upstairs is most likely little or no return air ductwork upstairs. You can blow all the cool air up there you want to but if you cant return the warm air back down to the furnace then it aint goina do shit. BUT, I cant see your problem from here. Second, get it in writing that your A/C will cool your upstairs to within 1 degree of the downstairs or they will fix it till it does or refund you some portion of money. Next, dont get too hung up on brand names. Its the installer, not the Brand that will make your system work effectively. Since your having cooling problems, now is the time to get a load calculation done on your home. If your contractor cant do it then send him packing. Lastly, why on earth would you futz with installing a good thermostat when you just spent however many thousand dollars getting a system installed? Im sorry but thats just plain stupid. Tell the guy to cut you some slack on the stat. He isnt going to give it to you for free but if the job is priced correctly he can afford to make a lower margain on the stat to get your work. Remember, if you install a stat yourself after the job is installed you may get charged for a service call during the warranty period. I know I most likely would unless it had absolutely nothing to do with the stat. Would you change out the radio on a brand new car you just bought because you found it cheaper at "Wal-Mart discount store?" Bubba
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Poor analogy because millions of people do exactly that.
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alix wrote:

This is a ducting issue. Neither brand of unit nor size of unit is going to correct this. If the t-stat is downstairs, then upsizing the unit will only provide the imbalance in temps quicker. There are several options for correcting this, the best being the addition of returns to the bedrooms. Or it may be as simple as undercutting the doors.
Here is some related literature:
http://www.eere.energy.gov/buildings/info/documents/pdfs/air_dist_sys_design-0782.pdf

See above. You don't want this guy.

Deflectors are a much less expensive option. You can by them at most home improvement centers. This will not however solve the temperature problem, it will only provide better mixing; a more even temp throughout the rooms.

See above. You don't want this guy either. More airflow may be in order, but a modification to the central return isn't going to solve the supply balance issue. You'll get more airflow into both zones, but in the same proportion as before.

Again, return air size isn't the problem. It may be a problem as far as capacity and efficiency is concerned, but it isn't the cause of the temp imbalance. The Trane guy may have been correct about the size, but I can't see it from here. I can tell you that the Bryant guy's plan isn't going to work as intended.

That's your call. If you want to DIY on part of the install, then they may or may not be willing to work with you on that. Your time is free, ours is not. My company wouldn't bargain with you on this however. On a new unit we install the stat, period! The reason for this is that we don't want you fucking up any of our equipment and then crying about it and threatening lawsuits when it was entirely your fault that the board is now fried. Don't be surprised if you and whoever you chose end up not getting along so well.

So? See above.

I did the same when it came to treating my new fence. Bought a Wagner sprayer and the wood treatment for a fraction of what they wanted to treat the fence for me. The time required turned out to be considerable however. (They were quoting mostly labor.) Normally I wouldn't have done something like that, but it wasn't my idea to install the thing, but I digress.
As it so happened a few of the slats warped (before treating), and they refused to replace them for me. I didn't push the issue. I still had enough savings left to replace a bunch of those bastards myself. But there is no comparison between a fence and a piece of gas/electrical equipment located within a house.
In the case of the t-stat, there is much more at stake, namely liability. Your house could actually burn due to a miswired stat. It is also likely that their price includes pulling a new t-stat wire. The warranty issue is however enough on its own to refuse the bid under your conditions. Even minus the new wire, they could lower the price, but they would have to add it back to the unit. The profit has to come from somewhere, where it is distributed on paper is sometimes just a formality.

I'd shop around until you get somebody else who knows at least the minimum basics about air distribution.
hvacrmedic
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alix wrote:

Are you sure you can buy a 2 stage T8600 for $106 on the web? That sounds like the price of a single stage model.
FWIW, you should be able to negotiate that $250 down to $150. That's what it would cost here (in Florida) for a 2-stage Chronotherm IV (or Vision Pro) if done at the time of system installation.
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And if your " handyman buddy " ruins it or cant make it work, then what. He aint you "handyman buddy" anymore and you pay.
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Thanks much to everyone for replying.
Re: the load calculation: Both guys measured the furnace and basement ductwork. The Trane guy measured all rooms individually and did look into the crawl space at the insulation; the Bryant guy took an aggregate measurement of the footprint both upstairs and downstairs. They both appeared to be doing lots of math; whether that math resulted in the load calculation is not clear to me. I will find out.
(As an aside - the first quote I got was from a guy who walked in, wrote down the numbers from the existing furnace, said "I'll get back to you," and left. His quote was cheapest of all, but I ruled him out based mostly on the fact that I couldn't even get him to stop to talk with me about the job... although I did ask the question about getting the AC upstairs as he was backing out the door. He basically said, "We can't do anything about that." Sheesh...)
Very good points re: the thermostat - thanks. I'd hate to invalidate the warranty or service contract over a few bucks. (BTW - Travis, you are correct. I was looking at single stage.) It might be worth noting that the Trane guy included a programmable thermostat (also Trane brand) in his quote at no additional cost. He also will also reinstall my existing humidifier (an Aprilaire 550, I think); the other gentleman proposes installing a new Honeywell electronic air cleaner for an additional fee. I don't know anything about "air cleaners," so I'm not sure whether it's worth going that route or not.
Regarding the returns: I know that they exist upstairs - they are positioned exactly opposite the supply registers in each room - but that's all I know. HVACmedic - if I'm reading the link you provided correctly, I have a "trunk and branch" config in my house.
So - I will get a few more quotes, and will be able to ask more intelligent questions as a result of your input. Thanks again for your help.
Ali
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