Thanks to everyone for your input. Based on the feedback from the pros so far, I see that next steps are as listed below. Please let me know if I've misunderstood or missed anything: 1 - Ask dealer to provide, in writing, load calculation support for a 2.5 vs 3 ton system 2 - Ask dealer to provide, in writing, that existing ductwork (both supply and return) is sized correctly to handle the additional CFMs provided load calculation indicates going up in size to a 3 ton condenser. 3 - Ask dealer to provide, in writing, that existing lineset is sized properly to manufacturer spec and ask dealer to warranty any future issues with lineset (critical parts are connections at each end) $1000 to replace is not advisable unless existing lineset is not properly sized. 4 - Get additional quotes on equipment noted in proposal #1 from other Carrier dealers (along with load calcs). Current dealer pricing is very high. Remove Greenspeed model 25VNA036A003 from scope given we have a gas furnace for the first floor (this is overkill) 5 - Existing proposal for backup heat model FC-2901N09 is satisfactory (9KW that is field convertible to 3 phase) Ask dealer to install staged heat strips and specify in proposal. 6 - Continue to use current 4 ton central A/C until it dies. Not necessary to replace at this juncture. 7 - Discuss lock out temperatures with installer to ensure proper energy usage. Some additional comments/concerns: @tigerdunes - in response to your last post, we are running emergency heat strip intermittently for heat. I have been turning the fan on upstairs to draw heat from the first floor furnace to keep temperature comfortable on second floor (around 68F) Thankfully, there hasn't been a need to keep emergency heat on constantly. @tigerdunes - thank you for suggesting additional equipment. In your opinion, is the incremental cost of the two-stage Infinity 25HNB636A003 (proposal #1) worth the investment vs. the lower priced systems you suggested? I'm trying to make the best cost/benefit decision since we do not have any plans to move from this home. If it were your home, what equipment would you choose? @mike_home - you noted early on that the proposal pricing for #1 seemed high @ approx $7K. Is there a price range that is more reasonsable for a 3 ton system provided everything else remained constant - same backup heat, infinity controller, using existing lineset? What about a 2.5 ton system? (i.e. $5-6K for 2.5 system is fair, an additional $500-$800 for a 3 ton system, etc) @mike_home - you recommended getting a 4 inch media filter. Dealer proposed upgrade to a Aprilaire 2210/2410 Air Cleaner for $300. Is this worth the additional investment or do you have another suggestion? @ryanhughes/tigerdunes/all - you indicated the existing VP 8320s could be reprogrammed and used. Since they are full touch screen models that appear superior to the SYSTXCCUID01-V Infinity controller proposed which isn't a touchscreen, I was curious to the advantages of replacing vs. using the existing ? What are the drawbacks? I'm very pragmatic about changing my filters every 3 months so I don't need a controller telling me to do so if that's the only advantage. @ALL - Should I only pursue Carrier dealers at this juncture for quotes on equipment? Since I have multi-speed Carrier 59TP5 Performance Series 95 gas furnace, I am assuming you all are recommending that I do not pursue Trane/Lennox or another manufacturer as it would create a mismatched system? This was the one point I didn't hear a lot of feedback on other than the Trane having true electronic demand defrost. Again, MANY THANKS to all of you for the invaluable advice.

Interesting, although they don't seem to publish any performance. If you were to use a standard MERV 13 filter of that size, it would be 0.1 resistance at 300FPM or about 1050 CFM. Most applications can handle that, which also puts you into the very low 90's for efficiency. There are other manufacturers of replacement filters for the Aprilaire unit such as AAF and Indigo. I know Indigo's A/A unit is a MERV 11. I donÂt care for their rack though, looks cheesy and would be concerned about bypass. As an FYI, I know many friends in industry that have gutted the track out of their A/A unit, add some foam to door and back, along with a gasket at top and bottom and use a commercial pleated cartridge filter sold by the case in my industry, with many choices such as Flanders, Precisionaire, American Air Filter and so many others.

Yeah, it doesn't show the size of the furnace anywhere in the 1st quote, all I can find is "SL280V 090V60C 2-stage 80%" everything has been 80k or 100k BTU so maybe one of those? I'll call the guy tomorrow and see if he can tell me. I'm really not sure about the house, probably a good 10 years or so at this point. Some of these quotes have a Fed Tax Credit and some have "and/or" Manufacturer Rebate. The first Lennox quote says $400 from Lennox + $400 from the power company. So $6,780-$800= $5,980 in the end. The guy that gave me the 2nd quote had a few other options, one was for a $10,000+ Carrier system but the other two quotes were: $6,912 Carrier PG92SAS60120D 92% 1 STG 120K BTU Payne PH13NB048000 4 Ton Condenser AC Carrier CNPVT4821ALA 4 Ton Evap Coil $8,217 Carrier 24ACB348A003 4 Ton single stage AC Carrier 59SC5A120S24-20 120K BTU Carrier CNPVT4821ALA 4 Ton Evap Coil I don't know why 120K BTU when everyone else was 80K but surely there's similar models that are smaller along that same line. All of these prices are assuming I'm paying full upfront, some quotes give 5% off if you pay in full, others took $500 off the equipment, etc. so I'm showing the lowest possible quote.

Oh, no way, a failure by you, someone who's helping folks in your spare time?! No way! (I hope you were joking.) By "not a single person mentioned", I meant like installers when they came to give estimates, not anyone here. No trouble, it's all a learning experience. Yes, I had a media cabinet installed, but it was a Honeywell. I couldn't convince my installer to get the official Ruud cabinet. I wouldn't even call the condensate issue a failure necessarily by my installer, because he is right that my sump pump should work in freezing weather. Just these furnaces still aren't common in my area, so I'm surprised there aren't more words of caution out there. (In fact, my emergency handyman who came out that night cause I thought something had burst -- services rental properties as his full-time job -- turned to me and said "I haven't seen this before but your furnace is discharging water.") My installer is considering a condensate pump and there's a slight issue where the outdoor temp isn't being read. But overall, I'm super happy with my 96% Ruud and EcoNet thermostat. The thermostat tells me whether it's running high or low stage, I've been told I'm spending too much time with it. I can't thank everyone here enough. In the end, I was able to find a great HVAC team. It's been quite the adventure. I'll post pictures soon. The duct work is a masterpiece, everything was turned 90 degrees because otherwise code required I create a service opening in the wall.