If you had a 4 ton outside AC condenser and it cooled the home to your satisfaction, then you need a new 4 ton AC condenser preferably with a new matching evap coil. Anything less and you are wasting your time. You can not mix an old evap coil R-22 with a new outside 410 AC condenser, just compounding your problems.

IMO

It is the inside unit with the heater that is 4 ton, 10 years old and working fine. the outside unit with condenser I believe was 3.5 ton and is now 2.5 ton. they are now not working together. the home is under 1200 sq ft .. sorry I dont understand terms beyond that. does that make sense ...do you still think I am wasting my time??? this is the AC guys idea to fix his mistake of not checking the sizing. Thanks for you response. :)

Thats right. The AC guy that replaced the outdoor unit did not make sure it matched the size of the indoor unit. The indoor unit works and doesnt need replaced. so in order to fix the problem he wants to replace the evap cool and txv valve. He says this will fix the problem and make it work. ?? thanks for any suggestions. I just dont know if I should let him do this.

He messed up. He needs to replace the outdoor condenser with either a 3.5 or a 4.0 ton unit. His proposed "fix" won't help.

This is far more complicated than those who responded on this board.

Number one: You say the home is under 1200 sqft.

a 4 ton unit for 1200 sqft would be grossly oversized, unless the house has windows in place of walls.

'I' as in 'me' can mix an old R22 coil to work with an R410a condenser. (I must be special gifted or something) It's true that not all coils you can do this with. The caveat is that the person doing the work must know what they are doing. You know they aren't just a keyboard warrior.

AFAIK, I am the only one on this board who actually works on, repairs and fixes residential HVAC units. Sure anyone can do it just like anyone can post to this board and recommend things you to do (many of them are just home owners)... your mileage like everything else will vary in life.

As I have said many times before this is why you hire a pro... but pro these days is tossed around like vegetable lasagna and 'free' all you can eat salad and bread sticks... you know because here you're family. Congratulations.

I service the Katy, Texas area (suburb of Houston).

It is a bad choice to mix coil for one refrigerant with an outside condenser of another refrigerant. Should always be a matching coil to outside condenser. Why take a chance on a shortcut like that?

IMO

We don't know if this was a 4-ton furnace set for 3 ton operation, and whether the old compressor was 3 ton unit. Then going smaller to 2.5 ton would not be so bad. We also don't know the size of the furnace (BTUs).

To answer your original question, a matched condenser and air handler will work if it installed correctly. Where are you located? A 2.5 ton condenser should be able to adequately cool a house that is less than 1200 sq. feet.

Did you hire an HVAC company to do the installation, or is this someone who does side jobs? Someone who has not paid attention to the size of the equipment should not be doing this type of work. If he can't do that, then I would not trust him to do anything else.

Can you provide the model number of the condenser you purchased? Once that is known then we can figure out the matching air handler. Then I would recommend you hire someone that is licensed to install the proper matching air handler.

Taking everything you said in consideration,it doesn't make good sense so I advise getting you money back,hire someone to do what's required and give the equipment back if it must be replaced. You are beating a dead horse trying to gain info that alow's directing an installer that doesn't know what he's doing. Stop before it get's worse.

Thank you so much for your input everyone. yes this guy is licensed ac. here in southern california. The guy that installed these systems 10 years ago installed them too large for this house and I dont know anything about these things. except what I have learned in the last several months becasue of the now problems. This guy just happened to not check on the sizes when he replaced the outdoor unit back in july. the size he put in is right for this house but doesnt match the indoor unit. thanks again.

"This guy just happened to not check on the sizes when he replaced the
outdoor unit back in july. the size he put in is right for this house
but doesnt match the indoor unit. thanks again."

Then he's incompetent for a couple of reasons. You don't normally just replace the "outdoor unit" without doing more. You paid for a proper job and didn't receive one. He needs to fix it with several additional pieces of new matching equipment properly, all properly sized and properly installed or refund your money.

It's a bad choice to mix coils?

But yet manufactures and AHRI do it to hit efficiency numbers don't they? Some manufacturer's make a 4 ton for an air conditioning system, but guess what --- that same coil is used for a 5 ton unit as well.

So if AHRI lists a 4 ton coil with a 3 ton condenser to hit efficiency numbers that's OK? When in essence you are placing a 3 ton condenser on also a coil suitable for a 5 ton air conditioner?

You could do 'everything right' --- replace everything... line set, evap coil, furnace, condenser and still have trouble. You could even suffer from compressor burnout within a certain amount of time with new equipment just as much as older 'mixed' equipment. Why do you think the manufacturer's give you a part warranty? Just because they are nice? Bad things happen, it's mechanical equipment for God sakes.

You can't get away from problems just because a manufacturer or some other group of people say this is the way it must be done. I am paid to fix equipment. A good amount of equipment I work on is NEW to a FEW years old. 'They all break' --- yeah I sound like a broken record, maybe one day it will sink in.

Why do it? MONEY, that's why. Not everyone has money to replace everything. BUT, they need to be more careful in whom they hire and whom they listen to or read on a forum board.

Why do it part 2? We don't want nothing fancy we just want the AC fixed. We plan to sell the home in a few years.

Why do it part 3? The house is a rental unit and the more we spend on the AC the less profit we make on the rental. (you own the home to make a profit not gold plate every fixture)

How to do it? Hire A PRO. It's the only way to go.

It's a bad choice to mix refrigerants of one coil to another coil?

I am not mixing refrigerants, I remove the refrigerant from the unit and make necessary changes so the new condenser will operate with the older coil. In some cases the older coil may not work. In those cases I will require a new evaporator installed with the new condenser. (They call this experience in knowing what will work and what will not --- you know the real reason why you use a pro to begin with.)

I service the Katy, Texas area (Houston suburb) I am a Texas licensed HVAC contractor with 24 years experience and I will be the one actually doing the work you hire me to do.

This is a interesting discussion. Let's see if we can learn some things.

First off the OP hired a licensed HVAC contractor. I think that is the definition of a "PRO". Maybe he is not really licensed, or is working under someone else's license. A license is no guarantee a repair will be done correctly.

The OP believes the problem is due to an incorrect condenser size. But there are more problems here than just incorrect size. If appears a new 410a condenser was installed, but the TXV valve and coil were not changed. I thought the TXV valve would have to be changed when going from R22 to R410a, but maybe it doesn't. If he didn't change the valve, then what is the likelihood the original R22 coil and line set was flushed out correctly?

So if the first guy really botched this up and mixed refrigerants, then is the new condenser salvageable? If it is, then what needs to be done?

again I appreciate the comments. It's getting a little complicated for me but anyway. I did try to hire another contractor to do what this guy has been suggesting because I got tired of waiting and dealing with him. This has been going on since july. the new guy didnt believe it would work. And from what I understood him saying, the new condensor does use a different type of coolant, but it is compatible with the indoor unit. However, It wouldnt be compatible with newer types of coolant without changing some things. I actually am going through the contractor lisence board as of a couple weeks ago and now this guy seems to want to get on in. But I dont feel comfortable with his idea anymore. I am going to insist he either take back his outside unit/condensor with a full refund, or replace the inside unit at a considerable discount. it is 10 years old and my last one lasted 19 years. so taking that into consideration Im thinking of a 30% discount on a new indoor unit. does that seem fair to those of you that are ac contractors? Thanks again.

This discussion brings up a broader question: you hire a licensed pro to do a job, which is not done right. This pro is obligated to correct the job, but if the correct way is much more expensive, then what would be the expected way to proceed? I don't think you should pay to undo the correct job, or for any incorrect equipment, but should pay for the proper installation. Pros, weigh in please.

If we have the true and complete story,I wouldn't alow the same people near my house,much less pay them to come back. I have never once installed a condenser without looking at and assessing remainder of system,not once,ever. Without having looked at rest of system,it's often possible to say the condenser (or compressor) must be replaced but only a fool would do the replacement without seeing if and how other parts of system contributed to the failure. Even if the technician was fool enough not to evaluate rest of system,what kind of idiot wouldn't know what tonnage/btu he is removing and that replacement must match??????

Well, the old condenser was 3.5 tons and appeared to cool the house adequately. The new condenser is 2.5 tons and doesn't cool the house adequately. Read into that what you will. Clearly we don't have the entire story here as some things make sense and others dont.

To argue whether or not someone has a license to do HVAC work or not. To consider what makes a pro a pro versus someone with just a license.

And how many licks does it take to get to the center of a tootsie roll sucker?

You only have a few metrics from which to judge someone who does this kind of work. You have to hope they are telling you the truth. I am very vocal about my skills and how long I have been doing this.

You can go to Texas license board and view my license number to show the number is mine. I have a youtube channel that has been in existence since very early when I started the business, another way to check. Will you be able to do these sorts of things for every contractor? NO. I take things to the 'whole nother level' as the old MAD TV skit portrayed. (Keegan Michael Key)

The characters on the side of my van, in my advertising were all created by yours truly. So outside of experience what is there: PASSION.

If a contractor is passionate about what he does --- what does that mean. That is the easiest way I can tell you the difference. (The difference you can't compare via what something costs or doesn't cost.)

If you're only in business to make money, passion is a waste of time. That's the point.

I'm here posting to a board on a post in which this is not my customer and probably never will be. Passion. (So you understand the situation.)

One of my characters is showing #1. This means more than what you think. Originality. I don't follow the mold. You either like this or you don't. I am a take or leave it kind of guy. I don't sell gimmicks, I sell service first and foremost, and I charge for it. Knowledge.

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Stipulations: If you hire me to change a part of your system, that part comes with a warranty. Part and labor if you want to pay for the extended labor I can sell you that as well - your choice. (conditions may apply)

The part or part(s) of your HVAC system that are replaced are covered by the warranty. Warranty does not include maintenance related repairs. Warranty does not include the older parts of your system.

If you want a system wide warranty, buy a complete HVAC system. Which will cost you more money, that is the trade off. Again your choice, you choose.

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Because I know what I am doing, you do not get to decide what is fair or not fair in the event of another failure.

So if the guy the OP hired failed to do this or that and *if* he admits that he made a mistake that's up to him to correct it. If I make a mistake I correct it and 99% of the time I correct it at the jobsite before I leave. So most of the time my customers never even know a mistake was made. This single advantage to the unskilled vs. skilled set me apart. How skilled is someone from a larger company? How will you know? *you won't*

Example: you install the condenser and go check the refrigerant charge and the pressures do not look right.

(If the pressures do not look right, it's not going to 'work') --- you have to *know* how to fix these kinds of problems. If you don't know, the result of this discussion on a forum board is likely the result. A HVAC installer is not likely to know, so you understand the complexities of this job and the difference from a installer, a tech and a licensed contractor. The installer is bottom rung. I do all three positions - and I charge for it. What do you want? A headache or something that works? Your choice.

Anyone can do HVAC repair, even a home owner. This doesn't mean it will be done right.

So saying you're a pro and actually being one --- what conclusions can you draw from this post?

#Ray is one in a million? two million? If I am not please direct me to a post on this board that has half the posts I do that shows them as being a pro and actually doing this type of work *professionally*.

Outside of all that I am not going to go down the path of thinking this guy you hired did something wrong, maybe he did, maybe he didn't ----- maybe the situation was fraught with failure from the get go because it sounds like the system is oversized for the structure.

This again is the part in which knowing what will work and what won't. I don't sell jobs in which I think there is going to be some kind of debilitating problem. Whether that helps or not? I'll leave it to the consensus of the board to determine.