I am not sure if other work is being performed. Here is what the quote says: We are pleased to submit to you an estimate and specifications for the installation of a Carrier 59TN6 Infinity two stage variable speed gas furnace with a Carrier 25HCB6 Performance 16SEER two stage heat pump Hybrid system to be installed in your home. Recover refrigerant as required by law. Remove and junk existing gas furnace, air conditioner and thermostat. Furnish and install one #59TN6A100E21-22 Carrier high efficiency Infinity series two stage/variable speed furnace with one #KGANP5201VSP Natural to Propane conversion kit and one #25HBC648 Carrier Puron high efficiency Performance series two stage heat pump with one #CNPVP4821ATA Carrier tin plated cased evaporator coil. The furnace has a 96.0% AFUE efficiency rating and a 100,000 Btuh input capacity. The heat pump has a 47,500 Btuh nominal cooling capacity high stage and 39,000 in low and a 16.0 SEER rating. New furnace to sit in same location as that of existing with a new return air drop, filter rack with hinged door, plenum and necessary sheet metal fittings to reconnect to the existing supply and return ductwork. Reconnect to the existing electric furnace circuit with a new switch and box. Reconnect to the existing gas line. PVC venting to be reconnected to existing. New condensate drain line to the floor drain with a new trap and clean out. New heat pump to be installed in same location as that of the existing. Furnish and install new outside fused disconnect as per Carrier and code requirements. Purge with nitrogen and reconnect to the existing refrigerant lines from the new indoor coil to the new outdoor unit. Furnish and install one #STAT-TP-PRH Performance programmable Thermidistat. Complete with necessary taxes, labor, wiring, and materials. COST Furnish and install the complete Infinity/Performance Hybrid HVAC system as described for Ten Thousand Eight Hundred and Ninety ($11,765.00) Dollars. This system qualifies for $200.00 Duke Energy rebate and a $150.00 Carrier rebate. OPTIONS Add one Carrier #GAPAAX1625 Infinity air purifier for an additional $1,550.00. This also qualifies for a $150.00 Carrier rebate. Net $1,400.00. I don't mind paying a fair price, but I don't want to be taken advantage of.

Gotcha. I will pass this along to the builder for him to have hvac guy do. I spoke to hvac guy about the $400 overrun vs the over-the-phone/options fax estimate (turns out it is not $1k -- $600 of that is the builder's problem for the 13 SEER base upgrade). He said that $200 of that came from needing to add 120v wiring to the power humidifier since it does not run off the furnace fan. We didn't specifically get to the other $200 as he stated that FILCAB was $450, and EZXCAB was $275. FILCAB is what was in the quote. So after a $40 MERV10 filter for EZXCAB we're now at $10 less than the upgraded quote. Interesting, especially since he previously said FILCAB was $225 -- and I had to set him straight that FILCAB could only take MERV8 filters from what I understand. I'll make sure the builder also gets a competing quote. And I am getting the complete model number of the coil in writing, of course.

So, we've decided to go with Bryant Evolution. The installation was done last week. It took 5 guys about 6 hrs to complete it. Everything went very well, but off course, only time will tell whether the installation was successful. Due to weather now in Maryland we didn't really have a chance to see AC or heat in action. So if anyone in DC metropolitan area is interested, I highly recommend this company. They are first in the Bryant authorized list of dealers. By the way, they were the only company that recommended we need 2 combustion grill openings since the gas furnace is located in closed storage room in the basement. Otherwise we would fail the gas inspection. After some negotiation the total cost (after instant Pepco and Bryant rebates) comes to $7K exactly. That include the equipment as described above, AprilAire 2410 filter cabinet, additional ductwork to accommodate new filter cabinet, servicing and re-positioning of existing AprilAire humidifier, 2 combustion grills, 10 years labor warranty, 2 maintenance appointments during 1st year and 12 month 0% APR financing. I think this time of year is kind of slow for HVAC contractors, I don't think they would be so willing to negotiate during busy summer months. Our attic HVAC system is also 16 years old, so most likely we will be replacing it next spring. I doubt we need something as sophisticated as Evolution or Infinity for second floor where we are during nights mostly. I'd rather spend more money towards insulating the attic. I'm sure I will be back with questions when time comes :-) Thanks everyone for your help! Happy Rosh Hashanah to everyone who celebrates it today! May your HVAC system never fail!

Thanks very much, tigerdunes. 3 tons makes sense to us because much of the upstairs cooling ends up downstairs, with the result that downstairs remains cool year round despite the dozen downstairs skylights (and six upstairs). We used to have a 5T AC on the downstairs system as well, but when it died we didn't notice downstairs getting any warmer and realized that the 3T upstairs must be cooling downstairs via the staircase, even more effectively than upstairs ironically. So really the upstairs AC is cooling a 3600 sf house (plus 900 sf basement which however remains naturally cool). Cooling efficiency for the upstairs system is important to us because (a) it spends far more time cooling than heating; (b) matter of principle: reduce our consumption footprint; (c) lower operating cost over next 20 years (for us and any subsequent owners of the house). System being replaced: 1988 Carrier 3 ton D&N (Day & Night) Heat: D&N 395BAW036060ABJA (3 burners, 71,000 Btuh in) Cond: D&N 568EJX036000AGAA (3 ton) Evap: label inaccessible Downstairs system that we're sticking with for now Heat: D&N 395BAW060120ABJA (6 burners, 143,000 Btuh in) Cond: D&N 568EBX060000AGAA (5 ton, long dead) Evap: BDP 518CXX057000BACA