>>> Our AC died two days ago. I am replacing the AC unit this weekend. I have 3.5 TON unit. The best quote I got is $2200 for new 3.5 TON unit (converting to 410a), new coil, new pipes (from teh coil to the unit), some duct work, 5 years warranty on the unit and 2 on labor.... Mick: Where do you live? $2200 for a 3.5t unit is a decent price for a low-end system. What brand and model # did they quote? It's hard to compare prices unless you are positive it is apples-apples and then even regional pricing are different (don't ask me how that's fair). Tarek: The quote above for ~$2400 is around what I was getting quoted this year to replace the coil in my 2.5t gas/electric packaged unit located on the roof. Replacement units ran anywhere from mid $3k to $10k for approximately the same level systems (Ranging from 3-3.5ton, 13-15seer, and 45-70k btuh on heating input). The Home Warranty can sometimes screw over the homeowner, other times not as bad. Sometimes the contractors are held (read: encouraged) to keep costs very low to keep business coming their way. So they are paid pennies for the covered part of the installation and they must recoup the cost somewhere. So it comes out in higher non-covered charges for installation.

If you are financing over a period of time, how much more per month will it be for the extra $300? Not much I assume. Now, grab a salesman (saleswoman-they have them now), and demand to know what is meant by SEER and what IS the difference between a 16 and 19? I know but you don't. You will be getting a ten year warranty with a new Carrier system, I assume? That is best. Parts are very expensive in all the new brands these days. Parts and labor warrantys are good, I think. You started out posting about the outside unit where the compressor is dead but now say Carrier infinity system ($9,000) with extras. So now you are talking about replacing both the inside and outside units plus some better ductwork (sounds like yours is too small)? Doesn't sound like such a bad price now. Especially if it is the Carrier 10 yr parts and labor warranty. Knock hubby in the head and tell him to wake up.

OP: Yeah, this is a scary area b/c that home warranty is paying the installer next-to-nothing fixed bid, and the installer needs to make some money. But on those thin margins, anything that can go wrong (not even wrong, but a little hangup) will eat that profit away. If that happens, you'll be into Cutting-Corners territory and you become one of those statistics where "bad installation" makes everything go wrong from leaky coils, to early compressor or blower failure, etc. You want your installer to make money and be happy to do a good job, just want it fair. I live in Central CA and the company I worked with (even via the AHS home warranty) published all their non-covered rates before a job was started. At least gave me some peace-of-mind seeing it on a professional carbon-press job cost estimate (not something printed from Word). If you want, send me a PM and I can share more info about this company and how their rates compared with a 2nd company, however much that'll help. Refrigerant Disposal (State Environ. Requirement) was $60 Disposal of old unit = $25 Title 24 Duct Testing/HERS Rater Verification = 400 -- any duct modifications are "per job" For Condensing Units/Compressors: "additional time for difficult access, lifting or inadequate work space" = 75/hr per person. For Furnaces/Air Handler/Coils: "disassemble old equipment, additional time needed" = 75/hr per person. They may make a few hundred bucks recycling my old gas-package unit, but it took a crane to get it off there (shared cost w/placing new one), and a couple guys to load/unload it, not making them much for a 22yr old unit. BTW, is it possible that $25 refrigerant disposal/recapture fee is probably $200 (recapture + flush lineset), less $175 discount for getting to recycle it/reuse or what not. What you've done is taken the value out of the recapture by giving the refrigerant to another vendor and leaving all the labor to flush the old lineset. But if you're tossing the lineset anyway, should there even be a charge? Good luck, FYI I'm an average Joe h/o, I don't work in the industry.

So yesterday buddy comes over to look over things with the a/c system and I think we've got things nailed down properly now. The superheat for the given ambient temperature and heat loading from the indoor coil was way off (5F) vs. the 14-15F that it was supposed to be so he had to remove some of the refrigerant (I was quite surprised how little he had to remove to get the superheat up) and we even went as far as measuring the furnace's CFM flow rating using a differential manometer. I'm pushing roughly 1000CFM across a 2 ton coil so which is a tad bit on the high side but my colleauge says it's a margin of safety for the a/c to not freeze over as we have relatively little humidity in the air would means that on the cooler days we wouldn't be heat loading the coil enough which could lead to freeze up. I personally would like to try running my furnace on the lowest speed to get the 855 CFM but I'm not sure how that will affect the superheat. Presumably I would imagine that if a system is charged properly using the superheat method for fixed orifice systems that blower speed shouldn't dramatically impact the superheat values to the point where they're completely out of whack. I would guess that superheat would rise but isn't that sort of a given? I mean hotter days for example would increase loading so therefore superheat should rise no? For the record the pressure reading on the manometer with the furnace on medium low with a 3M 1500 series filter installed has a -0.44 in wg static pressure difference. With no filter the static pressure diff changes to -0.55. Humidity was still somewhat of an issue yesterday night when it was raining but it was quite cool outside. I had to drop the tstat to 21C to force start the a/c on but after just 20 minutes the house was nice and dry and less stuffy. Just for the sake of my understanding does TXV technically do any better or worse job of temperature/humidity control over a fixed orifice system IF both systems were installed properly and charged to near perfection? I have a friend that is looking to install a/c and his contractor insists on having TXV and says that fixed orifice is evil and should never be used. I find that rather extreme to make a claim like that. I've tried to do my own research online and although it's a given that TXV is the way to go I think it has a lot to do with the fact that it will better protect the compressor from liquid flooding + it's more forgiving for techs that do an incorrect charge on the system - critical charge isn't nearly as important on a TXV system vs. fixed orifice. Thanks,