Our central air conditioning system has celebrated it’s 10th birthday by quitting. It is a Lennox 2 ton compressor and condensor. My question is how long should the compressor last and if it is fatal which brand do you replace it with? In our area there are few company’s that service Lennox and the people that installed it I have no faith in.
Jim G.
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Replies
Who told you it died?
What are the symptoms?
Ten years is not a long time for a central unit, and Lennox is considered on of the better names in the the mid to high cost range.
Tell us what the unit is doing, what you have checked, how you checked it, and anything else you can think of. There are several things that can go wrong, short of a compressor burn out, that can be fixed and you will get another ten years out of the unit.
BTW welcome to Breaktime. There are some very knowledgeable people here that I'm sure can help you out.
Please fill in you profile by clicking on your name in the to/from heading of the messages. Knowing where you are can help in recommendations for service and suppliers in your area.
Dave
It's a decent brand, but most of the parts that make it work are just about like everyone else's, so it is probably worth while to keep it and simply have a different HVAC company come look at it. It might turn out to be something more related to the original installation than the hardware.
Best of luck and stay cool
I'm with Dave. I just went through this. One thing I was told is if you can spin the fan you can probably fix it for less then fifty bucks.
In my case it was the capacitor.
Rock the Tipi!
I just replaced a 4ton carrier of about the same age last week...
if you pay for 2 service calls you've paid enough for a new condenser unit...
the brand thing is discussed here all the time... goodman being the low cost leader... but i can get goodman, coleman & bryant all about the same price...
a 2 ton condenser at my supply house is less than $600... prob closer to 450...
R & R on yours i would hope would be less than 1k total...
at 10 years old how much do u want to spend on it?
p
First of all thanks for the reply's. Now lets get to it. The compressor and fan in the unit (not the inside fan) would not come on. I did check to see if the fan spun and it did. Next I checked the obvious things circut breakers, disconnect box all OK. So it was time to uncover the electric panel on the side of the unit. With the power on the contact switch was humming which told me that was a good place to look, after shutting off the power and lowering the thermastat I more closely inspected the contacts and the related wiring, thats when I noticed one side (leg) of the switch was not closing as far as the other. Apparently a suicide had taken place during the evening and the carcass was not allowing the contacts to mate.
I removed the remaining body parts and with the power still off I took an ohm meter to the contacts to find that they needed some attention, there was some charring from the suicide that would not allow the compressor to start ( high resistance). After a few passes with some very fine emery paper to the contacts the compressor came to life.
The thing that was pointed out by many here was to keep it simple and not loose focus, take it step by step!!! I appreciate all that posted and I hope someone else may benifit by the information posted.
Many thanks, Jim G.
The fact that one company tried to sell you a new unit when a simple contactor was the problem should painfully illustrate why so many have such a poor opinion of HVAC (and other) contractors.
Regarding "best brand", as others have mentioned, installation is 99.9% of the equation. A Goodman unit installed by the book will outlast a 19 SEER Trane installed as quickly as possible by the charge em high fly by night outfit. Trane is not necessarily better than Goodman.
With the exclusion of some proprietary parts, the guts of almost any AC unit is the same. Some have nicer cabinets than others, but that is subjective.
Some things to keep in mind:
The new 13 SEER standard means that the indoor part must be changed with the outdoor part. Mismatced parts may work, but you will not get the SEER rating you are paying for.
Some lineset sizes have changed (larger) on the 13 SEER equipment. There is a good chance you will need a new lineset with your new equipment. Checked the price of copper lately? A new lineset will add several hundred dollars to the price tag. Cheap customers will ask do I have to do it, contractors that want the job may cut that corner to get it. The equipment will last the duration of the 1 year warranty.
R-22 is being phased out soon and replaced with R-410A (Carrier's brand name is Puron). Soon, you will not be able to buy new R-22 equipment. In order to operate properly, R-410A systems MUST be installed properly. That is a problem whan a significant percentage of HVAC contractors cannot install R-22 systems properly. You will need all new stuff with 410A. Did I mention that R-410A is about 3x the cost of R-22 at this time?
You can find out more on the R22 and R410A thing on the US government EPA website.
Not all installation problems are the fault of hack HVAC contractors.
A by the book air conditioning installation is pretty involved. That means it is time consuming. Hours = dollars. When a customer shops by price- and 99% of them do, a low hack bid will be chosen over a higher proper install bid the majority of the time. It is impossible to do more than 2 complete changeouts properly in an 8 hour day- including travel. Companies that are doing 3, 4, 5 changeouts a day are cutting major corners and violating EPA rules by venting refrigerant instead of reclaiming it.
You get what you are willing to pay for- most of the time.
Conversely, a high bid by a reputable company does not gurantee a proper install.
You must educate yourself and ask the right questions. Do not hire the company that can't answer them.
Edited 6/18/2006 11:47 am ET by danski0224
Excellent advice has already been given. I try to clean my outside A/C unit with the garden hose every month or so. It gets a lot of dust and hair in the fins and it's surprising how dirty they get.My outdoor A/C unit is 20+ years old and I called a Heating and A/C Tech last week who is a friend and asked him to service the a/c.He said "is it putting out cold air?" and I said yes. He said did you check the large copper line which runs into the outside A/C unit to see if it's cold? and I said no I haven't done that.I went out and while it was running I felt it and it's not cold.I'll have him come over next week and add freon or whatever. Maybe mine has shot craps - what's interesting is that the compressor has been noisy for three years now but it keeps on running.As you can tell I don't want to spend any money if I don't have to.I live in a three bedroom 1250 sq ft house and my electric bill is $100 per month year round.Good luck!^^^^^^
"The Older We Get, The Better We Were"
I realize that your equipment is 20 years old, but the "beer can cold" method of charging WILL NOT work on new high efficiency equipment.
Yes, you might get cold air, but I guarantee that the unit will be significantly overcharged.
Subcooling or superheat is the only way to do it right.
I'm not sure what you mean by the beer can method. I may be way off base but I'm wondering if I can buy a used outside A/C unit someday when my old one goes South.I think they replace A/C units every day and some of the old units may only be 5 to 10 years old. I'd like to buy one for a nominal price and have my friend come over and wire it in, charge it up, and do whatever we need to do.What happens to all the old equipment which is removed from the customer's home and hauled back to the HVAC company? Are they just sitting out back in a scrap pile behind the shop?^^^^^^
SNAFU (Situation Normal: All Fouled Up)
Hopefully that old equipments' freon has been reclaimed according to EPA requlations. If it has the gas is being recycled and the compressor has had a couple of holes drilled in the bottom of the canister for the oil to be drained and recycled too. The compressor go in one scrap metal bin or dumpster and the coil and any salvage line set go in another. All of it is then sold as recycleable scrap.
Does it happen that way? Only the contractor knows.
If you watch an HVAC tech. reclaim the gas, that is a good thing. If you see them free vent it, that is a bad thing for them, but could net you a hefty reward for turning them in. BTW the reward is part of the hefty fine he pays.
Dave
Hold the suction line until it gets "beer can cold". Guaranteed overcharge.
Ski,
Do you install or service air conditioner systems?
"...on new high efficiency equipment. Subcooling or superheat is the only way to do it right."
Only one of these is correct. It is not an either/or choice on a system with a TXV, which all "high efficiency equipment" will have.
Not all high efficiency equipment has a TXV valve. Some MFG's are doing 13 SEER with a piston. Last years 14 SEER by some also had a piston.
More are using a TXV now, which explains the TXV shortage happening now. Slapping a TXV valve on last years 12 SEER coil is probably good enough for 13 SEER without a redesign of the coil, which some manufacturers have put off. Tried getting a York or Goodman 13 SEER coil lately?
The equipment I am familiar with will not achieve the rated 14 SEER or above unless it is installed with a variable speed drive furnace or air handler. I bet plenty of "14 SEER" AC stuff is being installed without a variable speed drive.
"SEER" is also a joke if the ductwork is poorly designed and/or installed.
What you say is true. BTW, in what part of Chicagoland are you based?
I sold HVAC equipment including Goodman and York (actually Coleman, which is York, relabelled) up until two months ago. I'm based 90 miles WNW of Chitown. Here and there, IMHO, anything over 10 SEER is a waste of good money. As you kinda noted and I agree fully, SEER ratings are a poor way to "rate" a system, exclusive of the ductwork. The manner in which higher ratings can be acheived is detrimental to real system performance, especially in regards to dehumidification and IAQ.
Are all compressors now the newer type (I forget which is new and which is old - reciprocating vs scroll)? While the higher SEER ratings may not really reflect efficiency, I do know that the newer compressor types for higher SEER units are MUCH quieter than the old style units. I have about 6 tons of 13 or 14 SEER units, and standing next to them they are quieter than my neighbors unit which is 50 ft away behind a fence.
Some of the lower cost manufacturers still have reciprocating compressors in the lower end lines, and only in the 13 SEER versions, as far as I know. The "newer" style compressor is the scroll type, though it is not really new.
Many factors contribute to the noise created by a condensing unit. The simplest (cheapest) units are usually, but not always, the loudest. Real quiet units will have some or all of the following features: rubber compressor isolation mounts, a compressor blanket, a separate compressor compartment, poly base pan or base pan liner, internal sound deadening insulation, a larger slower turning condesner fan, areodynamically optimized fan blades (looks more like a sickle), and a scroll compressor. As the compressors have gotten quiter, most of the noise you hear on a newer unit is fan noise.
Edited 6/20/2006 2:47 pm by Tim
About 30 miles SW.
"Excellent advice has already been given."
That is true, but only by Dave.
i've run into that many times... magnetic contactor failure.. so much so that i keep a couple on hand... everything i have is 24v coil so i can even use 2 legs of a 3ph one if thats all i have... universal ones are cheap... i get em off ebay for usually less than $10...
glad you are up and running... i've also had problem with the time delay (keeps you from start'n & stop'n the compressor by move'n the thermostat off & on... usually a 5-10 min delay...) you can just bypass this as a temporary fix but again it's a $12 part...
I'm like many on here or all I'd hope... you expect the professional you call to do
A. a better job that you would yourself
B. have your best interest at heart
C. know more than you
D. if they don't know... to say so...
I know I'm at least 3 years behind in my work just from the lack of have'n anyone else who can do what i want done... I've extended trust to the untrusted so many times in hopes that they would become trustworthy.... but it just hasn't happened.... YET
glad you didn't get screwed
p
Wheew close call. I'm glad you got it fixed. Thanks for letting us know.
Rock the Tipi!
Ok, one (or so) more questions if I may. Now that the unit is running the discharge air temp at the ducts is 65 degree which tells me it needs a sip of R-22. Is it a standard practice to use a 2 ton compressor/ condensor unit with a 1 1/2 ton evaperator? The last time freon was added to the system (3 years ago) it was overfilled and the compressor had difficulty starting. According to the pressures it was not overfilled so the repairman who seemed to be knowledgeable adjusted to freon level by the duct outlet temp. He thought that the orifice was of the wrong size also. I don't think they used aTXV because the plenum is sealed and he also made a comment about that.
TIA, Jim G
View Image I only know one thing. If the motor spins it's probably something simple.
Rock the Tipi!
65 degree discharge air would be would be ok if the return air is 85+ degrees. That is a 20 degree drop across the coil and a target for unit performance, but not how you determine the amount of charge a unit needs. Of course a return air temp of 85 degrees means your pretty warm already :( A discharge air temp. at the evaporator coil of 45 to 50 degrees when the return air is in the 72 to 78 degree range is closer to normal operating parameter, but there are lots of other factors to consider even with that as a target.
Units do develop leaks at times, but that is not the norm. A leak means something is not right and needs to be fixed. Simply adding gas is a band aid to get the tech. in and out and on to the next job. They will be back because they did not find and fix the leak and you will pay them again and again until they finally convince you that you are pouring money down a gopher hole. Then they will sell you a new unit and make more $$ off of you.
If a unit leaks. Find the leak. There are numerous methods to locate leaks ( dyes, sniffers, bubble sprays, and visual inspections) that all take time that the tech. or company don't want to spend for some reason beyond me.
I no longer work on HVAC units and never did work on residential units, so I was trained to solve problems on commercial units, where unit replacement is a last option.
Maybe Tim will jump back in here and give you more expert advice.
Dave
Standard ARI (American Refrigeration Institute) ratings are based on 80/67 degF db/wb evaporator coil entering air conditions, and with an outside air temp of 95 degF. At the standard 400 cfm/ton, few if any systems will produce a 53 degF leaving air temp from the evap, which is what I design on to get good dehumidification and to set room airflow rates for 20 degree cooling, that is 55 degree supply air to cool and maintan a space at 75 degF db, 50% rh.
Jim G., the refrigeration charge is correctly set, in a fixed expansion device system (i.e. piston or orifice), based on three parameters: outside air temperature (db - which is dry bulb), inside air wet bulb temperature, and suction pressure/temperature at the condenser suction service valve. There is (or should be) a table inside the service panel of the condenser which lists the correct suction pressure at various values for the other two parameters. A competent service tech will acurately measure these before adjusting the charge. Anyone that does not is guessing.
Leaks are not normal or acceptable, but can occur over time at the service valves and at some compressor seals. The service valves should be fully "back-seated" and the caps, with good seals, in place. The evaporator coil, line set joints and other refrigerant components can sometimes develop pin-hole leaks. Some can be repaired, some cannot (economically). Ideally, the system would be evacuated, then pressureized with nitrogen to determine the location and severity of the leak. Once located and corrected, the system would be thouroughly evacuated and refilled. If there is a liquid line and/or suction line filter/dryer(s), they should be replaced. If there is not any in the system, at minimum a liquid line fiter/dryer should be added. The refrigerant in your system contains a mixture of "freon" and oil. If a system is not properly evacuated at startup, or if leaks in the suction side of the system exist, water gets in (or is never removed), mixes with the oil and creates an acid, which exploits any mechanical flaws in the system. Joints made with solder (even silver solder) instead of being properly cleaned, fluxed and brazed usually develop leaks over time, and 10 years is just about enough time for this to happen. If the service company/individual you deal with balks at any of this, says "Oh you don't need that" or gives you a blank stare, find another one. One competent tech, spending 4 hours or less should be able to do all of this, and it will be worth it.
Tim, Thanks for your time and help, I will be asking these questions and am eager to hear the reply. In your opinion and anyone else who might care to chime in is a residential system owner better off with a larger company who does many installations and repairs or are we better off looking for a small family run operation? Sometimes unless one co. comes recommended it is difficult to weed through the smoke.
Jim
The size of the company does not matter. Hack work and incompetence can exist in both large and small places. I know this from experience.
Do the systems work? Yes. Do the operate at optimum design? No. Does the customer get what they paid for? Not usually.
Is the customer willing to pay the price to do it right, or is there a compromise somewhere?
Your best bet is to learn how it should be done then ask questions that will reveal the answers you need to make a decision. There is enough stuff at http://www.hvac-talk.com to occupy your time for a while- the wall of shame is a must see.
Here are some pointers-
If they don't know what a micron gauge is or how to use one, walk away.
If they don't use a nitrogen sweep while brazing, walk away.
If they don't pressurize the system with nitrogen to check for leaks, walk away.
If they don't use a silver bearing soft solder like Harris StayBrite #8 and the proper flux, then walk away (there is no problem with soft solder if it is used properly. The burst strength of a soldered joint is higher than a brazed joint). Lead free plumbers solder does not cut it, and some shops use it.
A higher silver content brazing alloy is stronger than a low silver content, and it flows better. More silver is more money.
If they don't use a vacuum pump to evacuate the system.... Believe me, there are places that crack one valve to purge the refrigerant lines and call it good and open the other valve.
All this stuff takes time to do it right. You have to be willing to pay for it.
Edited 6/20/2006 7:00 pm ET by danski0224
"..is a residential system owner better off with a larger company who does many installations and repairs or are we better off looking for a small family run operation?"
Yes, one of those two, or something in between. There is no answer to this question. Personal referals might be a place to start. Someone who is upfront and open about what they can do, will do and recommend you to pay them to do. Someone that will stand behind their work. Two trains of thought to consider. A large outfit taht has been around and built a successful business has the experience, equipment, personnel and most likely a training/certification program. They also (hopefully) have a reputation and name to uphold. OTH, a small outfit is usually started by one of the brighter tech's from a large company, is growing their business and eager to do excellent work in hopes of establishing themselves in the market, developing name recognition and reputation of quality. In my market, having been on the engineering side and the equipment distribution side, I have dealt with most of the HVAC contractors in the area and know their work and their reputations. And the run the gamut of quality, from superb to "hacker deluxe".
Best thing for you to do is ask around and see what people's experiences are. Call some companies and have them come and take a look, ask them questions, see if what they say makes sense to what you've learned here.
Can I chime in on this thread and ask all what their position is on using the older R22 coolant vs. the new 410a (Puron)?
I'm getting a new system installed (have nothing now) and they are giving me the option of either or.
Two years ago, I would say it was a toss-up betweent he two. FYI, Puron is one manufacturer's (DuPont) trade name, the refrigent is R-410A. In four years, R-22 will no longer be manufactured or imported in this country, per the EPA, except as noted below:
"No production and no importing of HCFC-142b and HCFC-22, except for use in equipment manufactured before 1/1/2010 (so no production or importing for NEW equipment that uses these refrigerants)"
This will drive the cost of R-22 up, and the cost of R-410A will come down as large scale use and production pickup.
Now, I would recommend equipment that utilizes R-410A. Best to go with the obvious future of the industry instead of the soon to be past.
Tim, thanks. That's the way I was thinking of going too. Thanks for the info.
Thanks Tim. It has been a lot of years since I 've worked on HVAC units, other than routine PMs, and a lot more since since I went to classes on them (Trane in that little town in Wis.)
Dave
One part of the reason companies do not want to troubleshoot residential AC systems for leaks is the cost to the customer.
It takes time to find the leak, more time to reclaim the refrigerant to make the repair, more time to pressurize the system to check the repair, more time to evacuate the system, and finally some more time to charge the sytem properly.
So, how long does all that take?
Depends on how "correct" the repair and procedures involved are.
The retail labor rate hovers around $100 an hour for service work, so a 4 hour repair is $400.00 for labor only- now lets add the refrigerant and a filter drier at a minimum. Now a "simple" leak check and repair can approach $700.00 easily. No customer wants to do a T&M ticket, and the "flat rate" pricing is as high as the market will bear, so the cost ends up about the same.
That 4 hours includes travel time to the job, so now there might be 3.5 actual working hours to do the job from start to finish then hit the next one. That means hurry up because the boss has two more calls in line for you to hit.
If anyone has actually evacuated a system with a micron gauge, then you know that the hack method of running the vacuum pump for 20 minutes is a sham. If the repair involves reclaiming refrigerant, I can't see doing it RIGHT in less than 4 hours. Could be much quicker if it is leaking king valve caps or schrader valves.
Who is going to guarantee the longevity of an old system that has been repaired?
Before 13 SEER, it didn't make sense to dump that kind of money or time in a repair. Now that the whole system needs to be replaced (well, to do it right), more customers might do the repair thing instead of a replacement.
The $150 gas and go is a whole lot more attractive price wise to a retail customer, even if it is done every season. Lots of hack HVAC residential work out there to keep the gas and go guys busy- it only has to last a year. It is cheaper to fix a few leakers under "warranty" than to spend the time to install it right the first time at cutthroat builder bidding margins.
Businesses just pass their repair costs to their customers through higher prices.
My $.02
The retail labor rate hovers around $100 an hour for service work, so a 4 hour repair is $400.00 for labor only- now lets add the refrigerant and a filter drier at a minimum. Now a "simple" leak check and repair can approach $700.00 easily. No customer wants to do a T&M ticket, and the "flat rate" pricing is as high as the market will bear, so the cost ends up about the same.
That labor rate is about $25 higher than the commercial rate we pay where I work, but over all I agree whith your explanation of the "why they do that."
As I have said, I have never worked HVAC in residential, and only worked under the quidance of a good Master HVAC in commercial. Commercial equipment that we worked on was 4 to 20 times more costly than any normal residential system. At $20K to $200K even a couple of thousand easier to spend than replacing the units.
Dave
"The retail labor rate hovers around $100 an hour for service work, so a 4 hour repair is $400.00 for labor only- now lets add the refrigerant and a filter drier at a minimum. Now a "simple" leak check and repair can approach $700.00 easily. No customer wants to do a T&M ticket, and the "flat rate" pricing is as high as the market will bear, so the cost ends up about the same."Your post and Tim's above it are really good to read. We recently had a problem with our 10 year old AC. The coolant was virtually all gone. The technician was one we never used before, but was recommended by our trusty old HVAC guy who retired. He worked for 4 hours, found the leak at one of the valves, fixed it, recharged the system, and billed us around $750. I was afraid we were getting ripped off by a hack, but it sounds like he's one of the good ones. He was describing much of the same stuff that's mentioned here in this thread. We'll keep his number.
Accckkkk- kinda the same as my feeling after the ruptured appendix bill. But what ja gonna do? Happy to be a live but hatin the bill.
Your post and Tim's above it are really good to read. We recently had a problem with our 10 year old AC. The coolant was virtually all gone. The technician was one we never used before, but was recommended by our trusty old HVAC guy who retired. He worked for 4 hours, found the leak at one of the valves, fixed it, recharged the system, and billed us around $750. I was afraid we were getting ripped off by a hack, but it sounds like he's one of the good ones. He was describing much of the same stuff that's mentioned here in this thread. We'll keep his number.
Glatt, You might be doing a service to folks in your area to post his number and name so others can get quality work.
Just my 2 cents.
Jim G.
What a wonderful opportunity to switch it out for a nice 14 or higher SEER model - complete with your utility's rebate program picking up some of the cost.
She'll pay for herself over the next 2 or 3 years.
peteshlagor, with that in mind what brand(s) would you put on top of your list as being the most reliable and durable? How about the Mitsubishi and Sanyo brands, where do they stack up? You are right, there will come a time to replace it with a more efficient model but with the onset of summer at our doorstep now might not be the best time to get it done. Most Co's are in the "let's get to the next job" mode and I wonder if off peak might be a better choice.
Jim G.
Got no idea about your Q's, but it sounds as if Danski does.
You got a good point about seasonal work. I had them switch out my units in January, while the local ute's rebate was the highest.
One point about my negotiations with the installer. He said it'll cost $X,XXX and come with a one year warranty. I said I'll do it, but with a two year warranty. He didn't bat an eye and said OK.
"She'll pay for herself over the next 2 or 3 years."
That guess is nowhere near close to reality.
Considereing that a 14 SEER, 2 ton unit will cost a contractor $1500, at least, which they will install at 3-4 times including a new coil w/txv and lines set (required with the higher SEER unit using R-410A refrigerant and not R-22), maybe more. Minimum installed cost $4500.
A 2 ton, 10 SEER AC draws about 15 amps at 240 VAC, a 14 SEER, 10.5. IF the unit operates 10 hours a day, 100 days a year and electicity costs $0.10/kWh, the yearly savings would be $108/year. IF the rebate $1500 (unlikely IMHO) then simple payback would be over 27 years, far beyond the life expectancy of the equipment. Overall a very poor economic choice. A wonderful opportunity to burn some cash.
Edited 6/19/2006 10:43 am by Tim
Imagine that!
Mine didn't cost that much. My rebate was $450.
Where are you able to find $0.10 /KWH electric?
Your numbers appear well thought out, but maybe we're BOTH making assumptions we shouldn't?
I just found this on the web:
June 1, 2006
2006-R-0337
ELECTRIC MARKETS IN CONNECTICUT AND MASSACHUSETTS
By: Kevin E. McCarthy, Principal Analyst
RATES IN CONNECTICUT AND MASSACHUSETTS
In recent years, rates in Connecticut have been somewhat lower than in Massachusetts. From February 2005 through February 2006, the average rates for residential, commercial, and industrial customers served by electric company and competitive suppliers were 15. 49, 12. 52, and 11. 24 cents per kwh, respectively, according to the Energy Information Administration. In Massachusetts, the comparable rates were 17. 88, 16. 69, and 11. 18 cents per kwh. There were similar differences in 2003-2004 and 2004-2005, although Massachusetts' had a somewhat lower industrial rate in 2004-2005 than Connecticut.
Edited 6/19/2006 10:56 am ET by peteshlagor
So how much did yours cost, less the rebate?
$0.10/kWh is the national average cost of residential electric service. How much do you pay in the summer? I pay $0.08 plus a "summer demand" charge. Averages out to be over $0.10 between May and October.
I made assumptions, but they were conservative for the most part. With the exception of the very hot SW, the AC will likely operate half as much as I supposed.
IF electricity costs less, the payback will be longer. IF the usage is less than 1000 hours per season, the payback will be longer. IF you took my very conservative numbers and halved the cost of the install, and doubled the cost of electricity the pay back is close to 7 years. Still not quite "2-3" and not realistic either.
complete with your utility's rebate program picking up some of the cost
Ugh, bat taste in mouth. My utility (five years ago) mandated that you use their contractor, which locked you into their equipment and pricing, and a 10 year note to the Utility company.
So, rather than be "stuck" with a 12 SEER Ruud, and all brand new ducting, and for $5k over 10 years; I went with a 14 SEER Carrier for $3k which was paid off in two years. The carrier vendor I picked has been ok, they were a bit snippy when the outside compressor packed up in month 11--but they replaced it tuit suite (factory defect in the bearings, it what they told me later). Oh, and no charge for the complete purger & refill of the Puron refrigerant.Occupational hazard of my occupation not being around (sorry Bubba)