Yeah that's R22 and while that is a builder grade Trane unit that is probably out of warranty by now... typically those were sold with 5 year parts warranty. Because R22 Freon was already obsolete by 2013. With that said, this condenser 'could' last another 10 years, provided the coil repair work is done appropriately. The replacement coil needs to be a coil suitable for R22 / any coil can be retro fitted to work, but skill is required in choosing the coil. Typically home warranty companies are known for tom foolery. If the condenser was a dry condenser (nitrogen gas) it would say it was on the data plate in some manner. That's the down side in anything Trane or American Standard because they were one of the last manufacture's to switch over to R410a refrigerant. The R22 conundrum only effects you if there is a leak... otherwise it doesn't matter much. While the cost for it will only go up now that production has ceased, it's serviceable life is still around another 10 years or so. Without United Technologies Corporation heavy investment in R410a AC equipment development we would be no where near where we are today. R410a equipment has been available now for almost 20 years if you can imagine that.

I do not understand why he would oversize the BTUH of the equipment way above what the ductwork sizing will support at reasonable static pressures & FPM velocities. A tech may have to figure out another way to run ducts to those rooms. The linked page will provide some guidelines toward proper duct sizing. It appears you would not need much air conditioning tonnage. I am a retired HVAC/R Contractor since 1993 & do not operate an HVAC/R business or work as a tech anymore. udarrell _ 2007 Here is a link that might be useful: udarrell.com

Generally speaking, rule of thumb says a 5% savings with each one point increase in SEER. I don't believe it, probably close to 1/2 that. How did you arrive at $200 in savings? On new furnace, you will need a var speed blower or a high eff blower motor when going to a 15-16 SEER rated AC condenser and coil. If you are looking for payback justification, you will be wasting your time. There is a marginal savings with replacing everything over just the furnace now versus replacing condenser and evap coil at a later date. I think the better question is whether one can justify the difference between a 13-14 SEER condenser/coil combination versus 15-16 SEER condenser/coil combination. Because of manufacturer and dealer pricing, it usually is a difficult hurdle. IMO

Mike_home, thank you so much for helping. I agree that most of San Diego County has near ideal weather most of the year. We live 5.7 miles from the ocean, so we're not arid, but not humid most of the time. We've been having some really funky weather what with climate change and all. We have had heat waves into the 90s with onshore flow that were relatively dry and comfortable, but we've also had upper 80s with 80-90% humidity for 1-2 weeks at a time, which is pretty bad but really rare, maybe 2-4 weeks a year. To your questions: the house was built in 2005 and has 5368 total conditioned square feet. Here are the units we currently have: 3.5 ton - upstairs less master (2040 SF, 10 to 13.5 ft ceilings) 2 ton - master suite 606 SF (10' avg ceilings) 4 ton - lower floor (2722 SF, 10' ceilings) The house is 9 years old, current condensers are approximately 3-4 years old, furnaces and coils 10 years old. I have not thought to repair the equipment because it's "working" - you know, turning on, providing cool air, etc., just assumed it was because they were cheap SEER 10 units and therefore not working well, but I suppose it's the BTUs and not the SEER that determine cooling capacity. I'm not convinced four 8 x 14 registers (plus a few small ones for the bedroom and baths) are enough for the 2040 SF main upstairs area (of which 617 sq ft has 13.5 to 18 ft ceilings plus cool air loss down the stairs, I estimate a volume of about 30K cu ft. We also have 4 large windows, a 10 x 16' skylight, and 10' x 22' sliding glass doors. All glass is dual pane and tinted except our new 11 x 5' kitchen window. I believe we need more registers here. The master suite has another issue: in addition to the vents and return in the suite, the master unit feeds an 8 x 14 register to the living room, such that when just using the master unit, unconditioned air blows in from the living room under and around the door, drastically reducing the conditioning effect in the master suite. I strongly believe we need to disconnect the duct leading to the living room and restrict the master system to the master suite. The downstairs remains cool most of the summer and rarely needs A/C, but I suspect humidity may become an issue at times when we're in the 60s and near the dew point. I don't know if a dehumidifier wouldn't be the most cost effective solution rather than replacing the A/C compressor and furnace. I am also in the process of looking into sealing and insulation. They tore the insulation out of the attic to remove walls and install a new flat ceiling on the 2nd floor, and I'm pretty sure the insulation was not reinstalled properly, because even on 80-85 degree days it gets hotter than the outside. Downstairs stays almost 10 degrees cooler and almost never needs A/C use. The garage has never had insulation above it; completely virgin attic space, though the garage is not conditioned space. I believe good attic insulation would significantly reduce our cooling needs upstairs. Thanks again to all those who look and help out! David