A mismatched system is never a good thing, both for warranty coverage and longevity of the equipment. Sometimes it works, sometimes it doesn't. You just don't know what you're getting most of the time as far as efficiency and capacity goes. So as to your warranty question, Trane may not honor the warranty. Given those two options, the first option is certainly favorable with the variable-speed furnace, albeit 80% AFUE. You're getting the typical run around with warranty companies.

Thanks for your reply, Ryan,

I checked the model/serial number with the trane website and they only offered a 5 year warranty on that coil. I looked at the unit a little closer and based on dates that I can see, I'm pretty sure it was installed in 2001 so I'm out of luck there.

I could have them install a 90% or 95% AFUE, but with the mild winters here in N. Texas, it may take 10-15 years to get a return on investment.

I didn't see that you were in Texas. An 80% furnace doesn't seem out of place in your location.

You won't have any warranty issues just replacing the coil as everything else is out of warranty but you might get a better deal doing a system changeout in the off season also I would check the coil only changeout price that seems pretty steep and can't imagine the home warranty company going for it

Here is a link that might be useful: Air Conditioning Repair made easy

"... also I would check the coil only changeout price that seems pretty steep and can't imagine the home warranty company going for it."

I agree.

Thanks, I was thinking that that price was a little high too, but I'm not in the business.
FYI: The price includes:

1yr labor,10yr parts warranty,city inspection,secondary drain pan/float switch, freon filter, sealing...

My guess is that all of those items are standard with any company replacing the coil.

I'm hoping to get the home warranty company just to agree that there is a leak in the evaporator coil and give me a "cash out" option so I can have a good contractor do the repair. My guess is that I will not get anywhere close to the cost of the repair from them, but something is better than nothing. I didn't actually pay for the warranty, the seller did, so I am not as concerned about getting them to pay for it, as I am about getting a good system. In a year, I will not renew the home warranty, but I will have to live with my system.

I am leaning toward replacing the whole thing with American Standard. I don't mind paying more to have it done right, I just don't want to get gouged. Do you think the complete system price is fair?

Your complete replacement price is about right. It's hard to say without seeing the job and knowing the circumstances, and prices vary by dealer and area. The VisionPRO IAQ would allow you to have the ability to slow down the blower to dehumidify on demand if you're looking for better dehumidification (of course if it is setup to do so). Cash-out option sounds like your best bet.

Sounds to me like the coil replacement is high... but then again i'm not in your neck of the woods. I can tell you that i just replaced a 5 ton Goodman coil on a ranch here in S.Texas, in an attic, where the coil was too big to get out and the new coil was too big to get up in the attic. It took me close to a total of 8 hours work time, 4 hours drive time, coil, freon, dryer. My bill to the customer was a hair under $1,500.00

It sounds to me like they are pricing the coil replacement high so you think a full change out is worth the money.

My advice is to get a few more bids on a coil change out and if they are all close to the same price, then consider the full equipment changeout.
IMO

Hope this helps

sounds to me like either your coil is oversized for the condenser, its low on freon, or there is a blockage in the coil. best bet would be low on freon

So here is the update...
finally got the warranty company to send an HVAC company out. They "fixed a leaky connection", added freon and left. Never commented on the leaky evaporator coil. So much for getting them to "cash out" on the evaporator coil...oh well, thats pretty much what I expected...damn warranty companies!!

Well, i still want to change out the system, so...

I took the advice elsewhere on the board and got a second quote (good advice by the way!). I found a company on Angie's list and called them.

The full system quote for a Trane system:
Compressor: 4TTR4042A1000A
Furnace: TUD080R9V4K
Coil: 4TXCB042AC3HCA
Everything else is pretty much the same as the American Standard quote above, except I have 5 yr labor and 10 year parts. All of that for $3000 less!

I like the contractor, he seems trustworthy and knowledgeable.

Thanks for all your help!

Trane is mechanically similar to American Standard. Not a bad system. What thermostat? I recommend you look into the Honeywell VisionPRO IAQ thermostat. It's a very sophisticated thermostat that can slow the blower down to dehumidify on demand (if configured properly).

Hot as it is in Texas, you may want to look these sites over...usually will cut your power bill $50 a month during the summer.

http://www.trevormartin.com/about.asp

http://www.turbotecproducts.com/EPhome.html

http://www.p2pays.org/ref/11/10104.pdf

Gary