Air Condtioner Replacement

[jimmyjam]

I have an air conditioner that is about 15 years old and uses r-22 refrigerant.  It is in need of replacing and am in the process of getting quotes.  One of the contractors only wants to replace the outside condenser with a r-410a unit and convert the evaporator coils to be compatible with r-410a.  I always thought you had to replace the evaporator coils as well when changing refrigerants because of the difference in operating pressures.  Is a conversion advisable?

Jay

[daddo]

Double no.

These are the things done because of cost- only to find out a short time later, you must dish out even more money to fix what you didn't fix right the first time.

[Snipe Hunter]

We had exactly what you are describing done in the last house. No problems whatsoever. The condenser/compressor unit was replaced. The indoor unit was installed in 1978 and it works fine with the modification.

Is it advisable?I don't know but they do it every day and it works. Saved me about $2300.

[tomsteve]

We had exactly what you are describing done in the last house. No problems whatsoever. The condenser/compressor unit was replaced. The indoor unit was installed in 1978 and it works fine with the modification.

Is it advisable?I don't know but they do it every day and it works. Saved me about $2300.

saved YOU $2300.
new owners of the house, OTOH......

[blackhat]

Not a well thought of practice at all.  Multiple reasons not to.

[daddo]

The fact that many manufacturers won't warranty a mix match system speaks for itself. In the case of a Ruud compressor failure within 5 years- they wanted the indoor model numbers or no warranty.  They may take a 10 year warranty and drop it to 5 years on a mix match- etc.
If you have a heat pump- good luck with the warranty.

You will be doubling your refrigerant pressures in the system, playing a game with efficiency and so on.

Can you make it work? Yes. But I can also force a square peg into a round hole with a big enough hammer or take a 1955 Chevy radiator and fit it into your new 2016 F150.

I don't play these games with people. As a result, everyone is happy.

[jimmyjam]

Thanks, that is what I was thinking.

[Jack in omaha]

So I have a heat pump also use radiator heat in really cold times . It is a hybrid. It is 13 years old The thing is slow leaking freon at 4 lbs every 7 months. I was advised to replace the coil at about 2,200.00
What is the best way to proceed? They will offer a warranty on what they do. The outside compressor seems to be fine. The unit for heat pump and coil is in the attic. I think the coil is just old and slow leaking. Please comment and advise. Thanks so much for the same question as i am not sure if this is similar in nature. Everything is now functioning well after adding 4 lbs of freon.

[Jack in omaha]

thank you