The obvious question is what size and efficiency do you have now both heating and AC?

Post back.

IMO

Sorry, Tigerdunes, I should have included this information in my initial post. My furnace is a 50,000 BTU Comfortmaker with output of 39,000 BTU. One of the contractors stated my AC was a 2 ton model. I'm out of my league here. I rarely use the AC to save money. My only complaint about the furnace is the noise (the return air is adjacent to my living room) and the rooms farthest from the furnace being slightly colder than the other rooms.

I checked my gas bill as this winter was especially cold. My highest gas bill was $135.00.

Thanks.

You would want a load calculation for best sizing. Your condo may have strict covenants that restrict high eff furnaces. That would be your job to pursue this question. However, if my decision, I would install an 80% eff furnace with high eff blower. And yes it will be quiet. I would think a nice model like Trane's XT80 40 K size yielding about 32 KBTUs. Has a two ton rated blower which would be fine for existing AC.

IMO

sseverus:

Since your water heater is there, it can't be getting below freezing... which is the reason to avoid putting in a condensing furnace.

A high efficiency furnace is the way to go (92 or better). I disagree with tigerdunes, I've had nothing but bad luck with 80% furnaces.

Look at what rebates/incentives are available for high efficiency furnaces in your area also.

Be sure you use a furnace with an outside air intake- that's essential in this situation - you don't want cold combustion air being pulled into the unheated room.

Is the mechanical room insulated? If it is then I don't think you will have a problem. Ask your neighbor how is condensing furnace is vented and make sure the condo association allows it.

I think correct sizing is way more important than whether 80% or 95%+ efficiency. These small heating loads can be difficult to size correctly.

I don't mean to be disagreeable and sorry for previous poster's experience with 80% non condensing furnaces but they have been around for years, millions have been sold, and definitely not problematic.

IMO

I thank you all for your opinions.

Tigerdunes, you say the efficiency of the furnace is not as important as sizing. But determining the propriety of installing a condensing furnace is exactly the reason for my post. My condo is a cookie-cutter unit. Many here have exactly the same original layout, insulation, windows, furnace and AC. One of the contractors was involved with installing the furnaces when this condo complex was built. I would hope sizing wouldn't be much of a problem.

To answer a few of the questions posed: Yes, my mechanical room is insulated. I would have to get the Association to sign off on the install. This appears to be a matter of filling out the proper paperwork. Several co-owners have had condensing furnaces installed. My neighbor below likes hers and is very pleased with the noise reduction. I'm sure the furnaces are properly installed as the PVC air intake and vent are plainly visible.

Let me ask this question: If I were to lose electrical power for several days (maybe even a week) in the dead of winter (as happened more than once this winter to neighborhoods close by) would a condensing easily survive and start right up when power came back on?

I have received one quote so far and may as well post it now although the question of installing a condensing/non-condensing furnace is the primary reason for this post.

This contractor was very dismissive of installing an 80% efficiency furnace so he didn't provide a quote for one. He provided two quotes. One for a Bryant Performance 925s and another for a Bryant Legacy 915. Including gas incentives/rebates there was only a $260 difference so going with the Performance model seems to be a no-brainer. Here is the quote:

Bryant Performance 925s with D.C. drive (925sa36060e14), Bryant media filter, existing thermostat, Bryant 113 AC (113ana024000) with new lineset. Total: $6480 reduced to $6105 after gas incentives/rebates.

Thanks again for your opinions.

Okay sseverus,

A condensing furnace produces a small amount of condensate. There is typically a trap on the vent that you won't want to freeze. That's it really. But that seems like a very minor issue compared to your water heater and plumbing in that room. If that room freezes, you have a much bigger problem than the condensate trap on the furnace.

My experience with 80% furnaces has been that they are close enough to condensing that the exhaust gases condense in the flue - often destroying the metal flues over time. It's just an unnecessary issue when a condensing furnace is so readily available (92% are cheap, but also 95% or better) and you can vent with PVC - not to mention the gain in efficiency.

You will probably never see the payback between the 90% and the 95%... but it could be a selling point. I'd go 95% if it's really not much difference.

You may want to look at an Energy Star rated AC unit. You can get into the same kind of situation where rebates can make it a no-brainer.

Again, just make sure they install the furnace with an outside air intake pipe.

Jakethewonderdog, thanks for your response. You make perfect sense and have alleviated most of my concerns. I assume your reference to an "outside air intake pipe" refers to a PVC intake through an outside wall. If so, that is exactly what will happen.

Thanks.

As I said, correct sizing is more important than efficiency.

Clearly.you are oversized on existing furnace. So the 925S 925sa36060e14 while a nice furnace is both larger than your existing and has higher efficiency. If you are concerned about noise, you should be with an oversized furnace. Ask dealer for load calc. I believe this furnace comes in a 40 K model size.

IMO

Here is a link that might be useful: Bryant Preferred Furnaces

Thanks, Tigerdunes. What is the output of the 925sa36060e14? I'm not having much luck finding info on that model via search. I will discuss your concern with the contractor.

Thanks.

Do the math...Mdl number you listed shows 60 K size at 96% eff= 57 KBTUs.

What the heck is dealer even thinking?

Check my link. Model is clearly listed with Bryant Preferred Series. As said, I believe that furnace is available in a 40 K size with 2 ton rated blower. Dealer should be able to verify that.

IMO

Thanks. Didn't realize that was a 60K model although model number should have clued me in.