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mark2741 01-04-2013 11:02 AM

Gas Furnace Replacement Questions
 
I posted a month or so back when my gas furnace went kaput due to a crossover tube that was snapped in two. I checked with York and several online parts dealers and they confirmed what the service company said: the part was out of stock and obsolete/no longer produced.

I had it welded back together and then reinstalled it and the furnace is now working, but with it being 23 years old and me not wanting to go through this ordeal when the next part breaks, I've gotten estimates for a new furnace to be installed. I considered heavily going DIY but it's not a good option given me/my situation. While I'm handy, I'm just not comfortable going that route.

I've received too many estimates, but there were a couple that seemed so out of the park price-wise/goofy salesman types that I just disregarded them outright.

I'm in the Philadelphia, PA suburbs. 2300 sq ft house - 2 floor colonial.
Existing furnace is 96k BTU, single stage York, 80% efficiency.

Here are the estimates I've received (all are 'complete' prices including new chimney liner for gas hot water heater, new return drop, condensate pump, thermostat, etc.):

Contractor A:
Bryant 80,000 BTU, 96% 2-Stage with an X-13 High Efficient Motor (Model # 925TA048080S17)
$4600

Contractor B:
Bryant 100,000 BTU, 95% 2-Stage "with high efficiency ECM blower motor" (Model # 925TA48100E21)
$4700

** Note that both estimates are for Bryant Model 925T. What do the remaining numbers mean? Bryant's website only shows the 925T designation/model, so I'm assuming these are both the same furnace, only the additional numbers are due to the BTU difference?

Contractor C:
System 1: Carrier Comfort Series, single stage burner, standard fan 92% (Model #59SC2A100)
$3748

System 2:
Carrier 59TP5A100E21
2 stage burner
96.7% AFUE
single speed blower
$5420.00

System #3:
Carrier 59TN6A100V21
2 stage burner
96.7% AFUE
Variable speed blower
$5907.00

I am waiting on one more contractor - a father & son company (they live just a few blocks from me). They came out the other day and they were the ones who installed the existing furnace in the house. I expect to get an estimate from them within the next few days. They didn't really say much aside from reminiscing about the family that lived in my house before and when they installed the existing furnace back in 1989 : ) They seemed a little goofy and have a reputation for being a little gruff, but they're right nearby so if I needed service that would be a big plus. And the furnace they installed lasted 23 years so I am very interested to see what they come back with in terms of equipment/price.

Question #1:
The two contractors proposing a Bryant 925T furnace are differing in their BTU calc. One came in insisting that a 2-stage 80k BTU is the way to go, and then did his measurements and said he would confirm it when he inputted the measurements into the computer and let me know. A few days later I received the estimate for the 80k BTU. The other Bryant company came in, did his measurements, said he would input into the computer, and then estimated a 100k BTU 2-stage furnace. Why the difference? Unfortunately the other guys all said they would measure and do the calc *after* a commitment is made. They said basically that they estimate high (100k BTU) and then drop some if the actual BTU calc is lower.

I'm most comfortable with both of the Bryant estimates in terms of price and the guys that I spoke with. Problem is, they have the 20k BTU difference in size recommendation. Is that a major concern one way or the other? My existing 96k single stage furnace heats the house VERY quickly. For example, when it broke and was off for a day, the house temp dropped down to 61 degrees. When it was turned back on, it had the temp back up to 71 degrees in less than 10 or 15 minutes. So I'm leaning towards the 80k BTU being more appropriate, but with a 2-stage system does it really matter?

Question #2:
I really don't have the cash right now to get a matched air conditioner installed with the furnace. I *could* finance it but would like to wait if it makes sense. I've heard varying opinions: one contractor keeps telling me that I should go ahead and replace both. Others have said that the air conditioner, which is about 10 years old, should have another 3 to 5 years of good life left in it and that it would be a waste of money to replace it now/early. I see benefit in replacing it now but due to the cash situation I'd rather not. Is that a mistake? I realize it will likely be another $500 to $1000 extra when I have them replace it in 3 to 5 years, but that's acceptable to me. I replaced the condenser fan motor this past Spring, along with the capacitor, so I think it's probably in good shape for at least a few more years.

Thanks in advance for any advice, and sorry for the long detailed post, but I figure more info is better : )

jagans 01-04-2013 11:18 AM

Lets see what the Goofy Guys say. 23 years of good service speaks for itself IMHO. Besides, you have to be a little goofy after sniffing Gas fumes for a number of years. :thumbup:

HVACTECH96 01-04-2013 05:51 PM

925ta48080s17 925= series,t=two stage, cant remember what the a is,48 is blower size 4 ton,80 is btus 80,000, 17 is 17 inch wide.Bryant changed there numbering system, and I have sat down to study them yet.Basicly they have a 95% single stage with speed tap ecm motor,95% two stage with speedtap ecm motor,95% two stage with a variable speed ecm motor, and a 95% modulating burner with variable speed ecm motor.As far as proper sizing goes some guys still do the ole rule of thumb way and some take the time and do a true heatloss calculation.Bigger isnt always better.

Missouri Bound 01-04-2013 08:22 PM

Option B seems to be the most practical for you and what I would choose. (here's where I will get the flak) EVEN if tht unit is a bit oversized, and it probably is, it will function at a lesser btu rate when the thermostat is nearly up to temperature. It may run that way all the time once the initial temp is reached. This is a good feature if you use set-back because you have high fire to bring it back up to temp. and low fire to maintain on warmer days. And there is nothing wrong with getting several extimates as long as you do the required research to figure out what the extimates didn't tell you......and it looks like you are doing that.:thumbsup:

sammy37 01-04-2013 09:03 PM

Holy cow! At those prices I'm glad I learned at a young age how to do this stuff myself, I could never afford to pay someone that kind of money.

I'm in shock, didnt know people charged those kind of prices for furnace changeouts!

sammy37 01-04-2013 09:04 PM

But at the same time dont flame me, I do support contractors needing to make a profit, pay bills, shop rent, buy tools and support their families.:thumbsup:

carmon 01-04-2013 10:20 PM

$ 4000.00 and up is very standard in this area for a 2 stage variable speed furnace..... more if it needs lots of metal work.....

HVAC1000 01-05-2013 12:06 AM

just out of curiosity are you wanting to upgrade to a 90%+? if so then ya those $4000 prices are in the ballpark. but keeping it an 80%er would cut the price to a bit more than half.

carmon 01-05-2013 12:11 AM

80% really............. not allowed here...... 93% for retro and 95% for new homes.....:thumbsup::thumbsup::thumbsup::thumbsup: :thumbsup:

HVAC1000 01-05-2013 12:21 AM

oh ok i apologize i did not know the Canadian regulation, in the states we are getting a mandate from the Department of Energy making it illegal to sell or install anything below 93%. However this is only in the northern states ( http://gilsonusa.com/sites/all/theme...ceFurnace1.pdf ) but it doesnt take effect until May 1st of this brand new year. but i guess it all depends on where Mark2741 is located.

carmon 01-05-2013 12:24 AM

I loved 80% furnaces....... never thought I would ever sell a hi efficient..... well in the last 4 years sold 400 hi efficient..... hope they never quit....lol

HVAC1000 01-05-2013 12:33 AM

yes i really like hi efficient ones too they can just add up really fast on the customer from running a new flue and usually a combustion air pipe too plus having to figure out how to dispose of condensate other than that though i love them but the 80s are just soooo easy to change out i will definitely miss them later. so we are telling our customers to buy cheaper while they still can unless they want to upgrade. we've gotten a lot more sales. :)

carmon 01-05-2013 12:37 AM

I hear ya... we have no choice here...... hi all the way..... installs are a pain...... :(

beenthere 01-05-2013 10:05 AM

Quote:

Originally Posted by Missouri Bound (Post 1086455)
Option B seems to be the most practical for you and what I would choose. (here's where I will get the flak) EVEN if tht unit is a bit oversized, and it probably is, it will function at a lesser btu rate when the thermostat is nearly up to temperature. It may run that way all the time once the initial temp is reached. This is a good feature if you use set-back because you have high fire to bring it back up to temp. and low fire to maintain on warmer days. And there is nothing wrong with getting several extimates as long as you do the required research to figure out what the extimates didn't tell you......and it looks like you are doing that.:thumbsup:

Over sized 2 stage furnaces use more fuel then a correctly sized single stage, and don't provide any better comfort. In first stage they are less efficient then in second stage. Savings from a 2 stage comes from a slow even heat through out the house, not quick on off time.

Getting the right sized 2 stage so it has long run times in first stage makes a house much more comfortable, and saves fuel. Since most people don't need to set the temp as high due to the constant low heat.

Rapid recovery isn't as good of a thing as most think.

My own furnace takes 70+/_ minutes(depending on wind conditions) to recover 11 degrees when its in the low 20s outside. Once recovered it still has long run times and the house stays a very even heat through out.


The OPs house probably only needs a 70,000 95%er, but many brands don't make a size between 60,000 and 80,000.

carmon 01-05-2013 10:20 AM

bye 3/4 of an 80.....:eek:


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