Has the AC always behaved this way in comfort or has this been a gradual worsening of not maintaining thermostat setting over the years. You may be undersized by a 1/2 ton.

What size is the furnace? Where is it located?

I would want to see a load calculation for cooling and heating for the main floor system..

This system was quoted for a Louisville location last week and included Infinity Controller and box filter cabinet. Price was $7.5 K. You should be able to come close to that price in Atlanta area.

6405563 Active Systems INFINITY 17 PURON AC CARRIER AIR CONDITIONING 24ANB736A**31 CNPV*3717AL*+UI 1050 840 58CV(A,X)070-12 36000 13.00 17.00 1 RCU-A-CB 256 Yes

70 K Infinity 80 furnace, Infinity 2 stage 3 ton condenser, matching ALA evap coil, qualifies for Fed Tax Credit.

You would want your ductwork for main floor totally inspected as to size both supply and return to handle extra cooling CFMs if you moved up to a 3 ton system.

Post back.

IMO

This post was edited by tigerdunes on Tue, Aug 27, 13 at 16:25

Thanks for chiming in.
The a/c performance has been consistently bad on the main floor.
When I unkinked the 12" return two years ago, the inside temp went from 83 or 84 to around 81 on a typical 90 degree summer day.

I will have to check the furnace BTUs when I get home.
It's located in a large louvered closet in the middle of our finished basement.

Original furnace says 50,000 BTU/HR. I confirmed that it is 80% AFUE. Furnace keeps up just fine even at 20 degrees F outside.

Ok thanks for the spec'd Inifinity. I will have to get a quote for that whole system.

We have a quote for an Infinity 16 model 24ANB636A003 for the compressor and new coil model CAPMP36.

Came in at $4300 not inc the furnace.
With labor, equip pad, replacing fiberboard with Sheet metal plenum, and install (1) 8" return for the required CFM. Use existing line set.

Not sure why replacing the plenum- the old one has no mold and no air leaks. Plenty of surface area to add one more 8" return. There's room to add a couple more 8" returns if we wanted to.

The Carrier Performance 13 Model 24ACB336A003 came in at $3500. Seems pretty high for a nearly obsolete compressor/coil.

Media

Just so you know, you can't pair that Infinity condenser with your conventional existing furnace and expect to achieve the performance that one would expect from that equipment. Waste of money.

IMO

Thanks Tigerdunes.

Yeah I only looked at the Infinity condensor as 1 possible option. The thinking is replace the compressor/coil now and then later when money is not so tight, add the matching Carrier furnace.
The tech mentioned that the coil would swap in easily enough without having to reconnect or evacuate the lines again.

But I am not loving the idea of breaking this down into two parts. Seems like the less we handle the coil, the better. Not to mention additional labor costs vs whole system replacement at once.

Here in the Southeast we have been having a very mild but wet summer. I think I might just hang on for 2 or 3 more weeks, save my pennies and re-evaluate in the spring.
If money/economy is still a problem, then I can decide to go with A/C components only.
The wife and kids have all been trained to bang on the outside fan housing to get it working on start up LOL.

The rebate situation is unclear- not sure if Carrier will extend it next month (Sept.) or not.

TigerDUnes you mentioned the Fed energy tax credit for the Infinity 17 system that you spec'd. What kind of $ savings and how does that work or can you give a link?

I emailed the Carrier rep yesterday to add whole system quote and revise the a/c quote to reflect keeping the fiberboard plenum and factor in the cash discount but have not heard back.

Thanks a "ton" for your voice in the middle of darkness.

Fed Energy Tax Credit

Apprx $350 with the 80% eff var speed furnace and high eff AC

http://www.energystar.gov/index.cfm?c=tax_credits.tx_index

iMO

Here is a link that might be useful: Fed Tax Credit

This post was edited by tigerdunes on Wed, Aug 28, 13 at 11:37