80% Variable Speed 2 Stage Furnace

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Old 10-13-03, 11:33 AM
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80% Variable Speed 2 Stage Furnace

in attic.

So far I have met with several contractors. I am trying to heat 2nd floor only.
Here art their suggestions
1) put a 95% furnace 40K in attic. put the humidifier in the attic. (very pushy contractor)
2) recommended 92% 40K efficient furnace in the attic. Put humidifier in 1st floor closet. Would also put other furnaces in attic based on my preference but recommends 92% single stage furnace. He also gave me a quote when I inquired on a 96% efficient variable 2 stage furnace.
3) recommended 80% 100KBTU variable speed 2 stage furnace (coiled to existing central ac). I did not inquire him on humidifier. Furnace will heat 2nd floor and 1st floor although according to him the 1st floor will still need the heating system to be on.
4) coil furnace (do not remember BTU or efficiency) to A/C and recommend closing the vents on 1st floor
5) put a 80% two stage furnace in attic or a 80% two stage variable speed furnace in attic. Does not see a place to put the humidifier since he says humidifier in attic is not recommeded and a humidifier also would not work on 2nd floor due to lack of connection to a water line. Did say humidifier could go in bedroom closet but it would be noisy when it is on. When I asked him about it, he did not think the lack of a humidifer is a big issue.


- Based on what I have learned I am thinking Contractor 5 has the right idea? Do you agree or disagree.
 
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Old 10-13-03, 04:18 PM
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being in NJ makes sense for a higher efficiency heat system, although i would not want a condensing furnace in the attic though many are located there. humidifiers in the attic are a nono, looking for troule there in my opinion. VS is a great feature
 
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Old 10-13-03, 06:17 PM
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being in NJ makes sense for a higher efficiency heat system,

Any other suggestions. Originally, I was leaning towards a 90%+ variable speed furnace. ON other post, I was suggested not to do this. Now you say 80% is not efficient enough. Can you suggest any other furnace
 
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Old 10-13-03, 06:49 PM
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Someone suggested it is possible to put a 96% efficient furnace in attic. He saiid

you either need to add heat tape, or carrier has a freeze protection device, that is really cheap. also you must drain into the plumbing. cant go outside or it will freeze. i usually tap into the "stink-pipe" the vent for the plumbing that goes through the rooof.

- Currently the attic is unfinished and has a central a/c up there.
 
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Old 10-13-03, 10:24 PM
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I've posted on your other sight.. ..

Go with the 2-stage 80% variable speed furance in the attic, and NO humidifier in the attic! Again you got water! Waterpipe and below freezing temp= busted water pipe, and flooding!


If you need a humidifier just get one of those stand alone units and place it in the hall way near the bedrooms, and or near the larger return vent.
 
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Old 10-14-03, 05:03 PM
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i agree with jay... i would never put a 90% or a humidifier in the attic...period. saw that post on the other site, very good input there.
 
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Old 10-17-03, 12:06 PM
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The contractor does not recommend the variable speed furnace. He said the 80% two stage will run on 60% of capacity and it is not needed. Basically, my biggest concern is quiet unit. Any comments.
 
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Old 10-17-03, 03:26 PM
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If you want quiet, I will still go with varible speed.. Also with variable speed, your electric bill will DROP alot since the motor is running on DC.


With variable speed, you are going to get a nice soft air flow most of the time. and the demand isn't met at cerent time, the blower will speed up to meet the demand...


My aunt and uncle installed a Trane Varable speed, and my uncle swears by it. The house has never been soo comfortable, and the cold room the used to have is no longer cool..
 
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Old 10-18-03, 03:43 PM
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would the Bryant 80% 2 speed variable be the same as Trane in regards to performanace, quietness
 
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Old 10-18-03, 09:11 PM
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Pretty much yeah, they are going to be the same in a way..

Personly, I'd stay with Trane.. Not big on Carrier/Bryant.
 
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Old 10-18-03, 09:42 PM
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Personly, I'd stay with Trane.. Not big on Carrier/Bryant.
Can you elaborate on why you say this.


You said they will be the same in a way. What do you mean by this?
 
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Old 10-19-03, 06:53 PM
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You said they will be the same in a way. What do you mean by this?
ment for how the system runs, and how they work..



Can you elaborate on why you say this.
I used to work for a dealer who was a Rheem dealer, and been on a few service calls on Carrier/Bryant units replacing parts.. ect.. So another word, I done more parts replacement on carrier brand vs the other guys..


Trane/American Standard is my personal first choice, then Rheem/Rudd my 2nd, and then York.


But the main thing is the dealer who does the job right, and you are comfortable.
 
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Old 10-20-03, 01:29 PM
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price for Bryant 80% 2 speed variable vs. Trane 80% 2 speed

- with the media filter included, the price for the Bryant is expected to be about $1000 less than the Trane.


Jay, you recommended the Trane as a very quiet furnace. would you think the Bryant furnace also 2 speed and variable speed would be just as quiet. I obviously want a very quiet furnace.
 
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Old 10-20-03, 01:58 PM
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I've been around the Bryant/Carrier.. They are going to be quiet as the Trane..

Couple of things to look at from the installing dealer (both Trane, and Bryan)

-Have they done a heat load/lost on your home (shown papers) for the right size equipment?

-What type of service they have? (24/7)

-Able to get parts with no problem in the middle of the night or weekends?

-What kind of coverage and warrenty work are the dealer offering ,other than what Trane or Bryant offers for thier own equipement. (Exp. They will place you in a hotel/motel if not able to get the system up and going after X amount of time. Will they stand by comfort of your home, they will up/down size the system if you are not comfortable)

- Will they come out to a free start up and check up on your heating, and A/C system for X amount of time?

~~~~~

I know A dealer who installed my parents new furance and A/C, they did all the above mention things that another B dealer didn't.. Yes, that A dealer was more than the other B dealer, but like they say.. "You get what you pay for"
 
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Old 10-20-03, 04:15 PM
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heat load

Jay, the Trane guy said he did do a heat load. The sqare footage is only 850-900 square feet (only will heat 2nd floor)

H said the BTU would only be needed 17,700 BTU. However, he said the smallest possible BTU is 40K. The smallest made for the variable speed is 48KBTU.
 
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Old 10-20-03, 06:50 PM
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Man..... That's alot of BTU for what the call of BTU is needed..

Please refresh me here of what you got going on, and why.. since you got alot of open thread..



Isn't this for a whole house?
 
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Old 10-21-03, 04:07 AM
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I am trying to heat the 2nd floor of the house only. This area consists of 4 small to medium size bedrooms and 1 bathroom. the biggest being 12*17. total sqare footage 850-900 sqare feet


ANother issue is I have been told that with the 80% furnace uses the surrounding air for combustion and that due to this I will hear the flame. Will the flame (burner noise) be heard all the time or only when it turns on.

I was told that since that since the 90% furnace is a sealed combustion, there is a plate around the burners and that no burner noise will be heard at all.
 
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Old 10-21-03, 04:47 AM
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Isn't this for a whole house?
See my post above.

I will try to keep questions on this thread
 
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Old 10-21-03, 06:44 AM
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Ok, Is there already vent going upstairs from the main furnace? Or you don't want to be trying to bring new ducts upstairs from the main furance?

True, the 90% burners are going to be quieter.. But with you putting the 80% up there, you won't hear it since you have insulation in the attic and that will cut down on the noise tranmison.

Are you planning on adding A/C to this unit in the attic?



I am have a feeling you may end up feelig not comfortable with this set up since you have a small area, and the furance can only get so small. Why I say that?

Your system would be oversized.. Even on low fire (31,000BTU), you are going to get a blast of heat out of the vents, also this will cause the unit to short cycle. Short cycling will shorten the life of the unit, and waste of gas. and I bet you 2nd stage will only come on 1% of the time.. So you are not getting it's full value out of the system.. (JMO)
 
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Old 10-21-03, 09:01 AM
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Ok, Is there already vent going upstairs from the main furnace? There is no main furnace.
Or you don't want to be trying to bring new ducts upstairs from the main furance?

True, the 90% burners are going to be quieter.. But with you putting the 80% up there, you won't hear it since you have insulation in the attic and that will cut down on the noise tranmison.

Are you planning on adding A/C to this unit in the attic? There already is a/c in the attic. A few of the contractors recommended
linking the new furnace to the existing a/c.

I am have a feeling you may end up feelig not comfortable with this set up since you have a small area, and the furance can only get so small. Why I say that?

Your system would be oversized.. Even on low fire (31,000BTU), you are going to get a blast of heat out of the vents, also this will cause the unit to short cycle. Short cycling will shorten the life of the unit, and waste of gas. and I bet you 2nd stage will only come on 1% of the time.. So you are not getting it's full value out of the system.. (JMO).

- I realize it is not ideal. Do you think now that it should only be a 1 stage furnace?.
 
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Old 10-21-03, 12:05 PM
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I was told by someone else a 40-42K is recommended.
 
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Old 10-21-03, 06:49 PM
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Is the current A/C in the attic just cooling the upstairs, or the whole house?

If it is used for the whole house, then put the furnace on to that unit, and use it for the whole house.. I take it you have hot water heat now or electric baseboard?


yeah, would be almost better off with the single stage. but they are not going to be as quiet... and not going to get your varible speed.
 
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Old 10-21-03, 10:11 PM
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The A/C cools the entire house. Option 3 on the contractors I had come to my house was :

3) recommended 80% 100KBTU variable speed 2 stage furnace (coiled to existing central ac). I did not inquire him on humidifier. Furnace will heat 2nd floor and 1st floor although according to him the 1st floor will still need the existing heating system to be on.


I had thought others on this site did not recommend #3.


"but they are not going to be as quiet... and not going to get your varible speed."

- I realize the advantages of the 2 stage furnace as I seek a quiet furnace. However, will the variable speed really make it even more quiet and why? The contractor who tells me it will be $400 more is trying to talk me out of it.
 
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Old 10-21-03, 10:37 PM
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Ok, now i understand ...

I am sure there were some misunderstanding here..


What you ment by the existing system to be on on top of the new VS system?

I don't see where people say didn't suggest #3? Maybe the didn't suggest #3 cuz of running current system on top of the new VS system..


How old is the current A/C system you have now? Is that in the attic as well?
 
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Old 10-22-03, 07:57 AM
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the A/C is 12 years old. An older trane model.
 
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Old 10-22-03, 08:12 AM
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It's old.. but not that old.. Does it do a pretty good job keeping up and all?, and is it pretty comfortable around the whoel house with it?


If so, then i would just put a new furance into that, and have the old coil cleaned up when you have this done.. Then you can get your variable speed blower, and 2 stage heat.. Also, we are not going to worry about over sizing of the duct work, and also you are not going to have a bunch of hole in your ceiling upstaris and ductwork in the attic.

What were you using in the past for heat source for the whole house?
 
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Old 10-22-03, 11:01 AM
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from a post 1 year ago

HEre is the story:
I am in a house which I bought recently with very noisy baseboards. The baseboards have been bled a lot, had other work done to fix them (including a Spiro Vent) and nothing gets rid of the loud COnstant Banging noise. EVEN the Spiro Vent did not elimintate the noise.

Therefore for a quiet system that I desire, I am going to have a contractor put a furnace in the attic. I have spoken to a few contractors and gotten 2 completely different ways to do this. Please note I do have central AC, a 4 zoned heating system (1 for the upstairs) and have vents on the ceiling in each room for the existing central AC.

One way I have been told by 2 contractors that a furnace can be put in the attic is by installing a horizontal Lenox furnace which would be attached I think to the AC by an AC COil. In addition, a new flue pipre would be installed. (the contractor said he will remove the existing air handler and replace with furnace and coil. The contractor said the heat would come out of the existing AC vents. I want to keep the 2nd floor its own zone. The contractor also said that when the heat is on I would need to close the AC vents on the first floor so no Heat enters the first floor. ( I am just wondering if this still means that heat really will be going to the 1st floor and just not being allow to escape?) Two contractors recommended to do it this way and quoted 4150

The second way I have been told by another 2 contactors is to install either either a Bryant or York furnace in the attic (completerly separate from th e AC). Then new ductwork would need to be done only on the second floor. He suggested 1 new duct per room on the second floor and 2 new ducts in the bedroom. The contractor using the Bryant furnace quoted 4500 and the contractor using the YOrk furnace quoted 5700.

I would appreciate any input.

- I fully realize that baseboards are supposed to be a superior heat source but after putting over 1000 in trying to fix this baseboard, I am not willing to keep putting money to fix it as no one can guarentee that what they will do will eliminate the very loud noise from the baseboards. I have been told by 2 contractors that no matter what they do to the baseboards they do not think the noise will go away so I am definitely going to get the furnace - I am just seeking advice on the furnace installation.

- 1 year later - We had hoped to sell the house already but are still here.

This was posted 1 year ago. At the time this happened we were planning to have the work done but due to a job layoff were unable to afford it and had a terribly cold winter. Now, we must act.
 
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Old 10-22-03, 11:04 AM
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response previously received

My choice of the two options you offered, would be to go with a separate unit for heating the second floor and leave the existing system alone.
If you were to install a new airhandling unit with heat and a/c coil on your existing ductwork, the air must be balanced for the airconditioning load while delivering air to both levels. When you shut off the air to the main level for heating, you will have way more air than is needed to heat the second floor. You will then have to reduce the air flow in the entire system to keep the air flow at a reasonable level for the second floor. This is not practical, and so for this reason I don't think this is the way to go.
 
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Old 10-22-03, 01:31 PM
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I honeslty think to keep the cost, and buget down, just use your current ductwork for the A/C for the new furance.


and use that for your main source of heat, and still use your hot water for back up.
 
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Old 10-22-03, 01:47 PM
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contractor #3 wanted to install a 100K btu 2 speed variable Trane 80% and his cost was about $1600 more than the next lowest quote. Perhaps if he was putting in a smaller unit it would be more comparable or cheaper.

The quotes I had last year using the coil method were no cheaper than putting the furnace by itself and doing new ductwork. Of course, each estimator had his own way of doing thing.
 
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Old 10-31-03, 12:48 PM
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Jay and others, Thanks for your replies. We are installing electric baseboard heat in bedroom next week for a few hundred. If I am not happy with that I will have the variable speed furnace 80% installed in a few weeks.
 
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Old 10-31-03, 04:22 PM
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That's a good ideal go with that and give it a try.. You may get some ticking sound when it first starts up, but nothing you can do about it. It's the metal heating up and expanding.

Keep us posted! :-)
 
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