I would agree with above with minor exception:

17 years is near useful life of the unit. Of course I know they can last longer... but 20 years is a good life for an AC.

Leaks can be fixed, but it's not likely to be a lasting fix in this situation. A unit that's 17 y o develops a leak... something has worn, eroded, corroded, etc. My guess is that there will be more leaks. Finding a leak (say in the evaporator coil) can be a bear.

You will need to replace the AH, condenser and line set.

I think the quote is way out of line also.

I agree about average age of AC system. Still the XE1000 10 SEER was a great Trane AC condenser. Line set should be replaced but if correct size and in good condition, it can be flushed according to industry standards.

also looks like OP received a gas n go service. Totally unprofessional. Was any effort made to locate leak, maybe dye was installed? I doubt it.

IMO

Did you get a written estimate? Do you know what equipment and service you would get for $12,000?

Re: line set... If I'm going to spend the money to replace 90% of the unit, I'm going to do the entire thing. You are right, but I wouldn't want to rely on the tech flushing it correctly or that it's in good condition.

Get your 3 written estimates. Preferably without the gold plated condensing unit...

On the linesets, nothing is wrong with flushing if done correctly and lineset is in good condition and is the correct size. But if replacing, keep the old lineset and sell it to the scrap yard for the copper value. Yes, worth the effort!

IMO

LOL, copper scrap efforts rely in quantity. It depends how much you have (truck load) versus how far you must drive. ($2.50 a gallon for gas, what is your time worth to you, etc.)

Most line sets are 15 - 30 feet. You may wind up with around 10 pounds. At current scrap price for #2 copper you're looking at around a whopping $23.00 in this scenario, but hey they will pay you in $2 bills! Woohoo!

Figure in your gas cost, how long it's going to take you to possibly sit in line at the scrap yard and you'll be making far less than minimum wage.

The difference is that when I go to the scrap yard, my vehicle is FULL of scrap. This is the only way it's worth it.

Worth the effort? Think ahead.

repair vs replace for this scenario really comes down to how long you plan to live here. Less than 5 years? Repair, just realize this may cost you more in repairs.

Long term: 10 years or longer. Replace it. This system is a 10 SEER unit. In the south an entry level unit will cut your electric usage by 40%. Depending on your utility rate it could pay for itself in about 10 years, maybe less.

Thanks for all this great advice. Basically the estimate is to just to replace the existing equipment with this: Trane condenser #4TTR4036 and this: Unico air handler unit #UM3036. No other service. The ductwork is all there, the new airhandler would have to tie into the exsting ductwork, but we are not adding any. Is there any industry rule of thumb based loosely off the value of the equipment installed to estimate installation cost? What is a reasonable range for a job like this? Of course I am going to get some other estimates. Also, I am wondering if the charge for the gas was reasonable... $400 for what took about 20 minutes to do. I am feeling pretty lousy about that but I really have no frame of reference. One thing that bothers me is that he told me that it probably wouldn't work and the thing seems to working fine now a week later. If it had a serious leak, how long would it take to stop working? It is definitely nearing the end of its life. The Trane system seems to be the cadillac for this kind of set up. The pricing on 3 ton systems at Home Depot is much less, but they don't carry Trane... the pricing online for that equipment is not at all transparent. Any ideas about a reasonable trade off on cost/value? Super helpful and thanks to you all.

Why a Unico air handler? Is this a high velocity system? This may explain why the quote was so high.

General rule of thumb is the installed price is twice the price of the equipment. The costs can be higher if the installation is difficult.

The leak may last a few weeks or a few months. The price of R22 will continue to go up until it is no longer available. You are paying for an expensive refrigerant. The Trane condenser is a single stage with an approximately 14 SEER rating. Not exactly a Cadillac.

Get more quotes. Where are you located? If you can hold out until fall you should be able to get better service and a little better pricing.

No Unico air handler unless a specific documented reason...

IMO

So here is a question that occurred to me. Knowing the set up, is there any new condenser that work with the existing old airhandler? That would save boatload right there. The airhandler does not seem to be having any issues at this point. Stated otherwise, have they retired all condensers that would work with this airhandler (one that works with the Trane XE 1000)?

No, and not a good idea either!...

If you're replacing the air handler, replace it with the same brand as the rest of the equipment. Makes absolutely no sense (for you) to mix n match components.

Pricing is very regional but the price you were quoted is about twice what I would expect for a builder grade Trane. Get at leats 3 more estimates.

for above poster, the XR14 AC condenser is not a builder grade Trane. Depending on configuration, up to 15 SEER.

IMO

For David....coming back to your question, your old system both condenser and air handler are for R22 refrigerant. Your new condenser will be R410 refrigerant. You can not match a 410 condenser with r22 air handler. That's why you will need a complete matching system.

IM

In some cases you can not use an older R22 indoor unit paired with a newer R410a condenser. In many cases these kinds of conversions are a bit on the risky side, as you need 'SKILL' to do the conversion.

You will probably lose a little efficiency because the system is not matched, but if you have a matched beautiful looking system you may not hit the efficiency numbers anyway if the work is done inadequately. Two sides to every coin, if you feel me.

The efficiency you lose by not having a matched system is small provided that the install is done appropriately / line set sizing is adequate / duct work is adequate / system charge is done properly. All these things take skill and require knowledge.

For obvious reasons, namely being the cost of equipment it can work. I have done this many times, including at a home I live at now (temporarily) as I make changes to this home as my heat load will be changing at this home.

The other side of this is that older copper coils were made much better than anything today. If you put in a new system and the system leaks refrigerant in the indoor coil, your efficiency numbers are a pure myth with that of a quote unquote 'matched system'.

So sometimes you have to read between the lines. I do not recommend 'ANYONE' buying equipment on line. If you buy it, the warranty (if needed) falls on you the buyer.

Work of this nature stated in this post requires not only skill, but also in depth knowledge of ALL BRANDS of air conditioning equipment. Not just a select few. Because you don't know what to buy, it is never advisable to buy products on line.

A fan boi, should never be used for services of this nature.

I service the Katy, Texas area.

"for above poster, the XR14 AC condenser is not a builder grade Trane."

OK, bottom of the line (unless you live in a northern state where they sell the XR13 as the bottom of the line).

Maybe from a SEER point of view, but definitely not builder grade!

IMO

;)

Had this same problem, with Trane XE1000 system. 22-years old. Got complete new replacement for 5200$, including install. But system was easy to get to, and accessible from all directions. Upgrade to R410 is automatic.

I just got a quote for the same, $4644. That $12000 estimate is insanely high.