Question about Converting R22 to R32

[exmaxima1]

My Lennox Elite 13 is now 26 years old and probably living on borrowed time. I'm looking into upgrading from the R22 system to a newer R32 refrigerant. Many installers are quoting installation using my existing R22 copper lines. They claim it is normal to flush and reuse the lines.

Is there anything wrong with using the old lines?

 

[Firebrick43]

Depends where and how they are ran. The old ones could be significantly corroded where it passes thru concrete or touching organic mater/certain chemicals are allowed to touch it and could cause pin hole leaks.

Or it could be perfectly fine.

If you do replace them insist on a good line set with black rubber foam insulation like mueller. There has been enough evidence that the cheaper poly foam (white) is breaking down quickly and causing pin hole leaks.

 

[bob smith1]

It is normal, but lineset should be visually inspected as much as possible. Let your pocket decide on a new line set if it looks good. I have no issue with it. BUT, demand that the lines be 'pigged' or swabbed to remove any residue or oils. It's a great time to clean them up, NOT just blow some N through and call it good.

 

[exmaxima1]

One more issue. My system is 3-ton and it honestly does the job though it runs quite a bit at times. The online calculators say I need 5 tons for my 3000ft2 2-story house. Would the same lines handle a 5-ton unit?

 

[bob smith1]

One more issue. My system is 3-ton and it honestly does the job though it runs quite a bit at times. The online calculators say I need 5 tons for my 3000ft2 2-story house. Would the same lines handle a 5-ton unit?

You need to lean on your installer more than some online calc. It is NORMAL and PREFERRED that a system run nearly non-stop in the heat. Sounds like 3T is sized right and 5T is an insane jump!

 

[exmaxima1]

Thanks!

 

[fitter30]

Nothing wrong with flushing a line set. Insulation outside should be wrapped with line set wrap to keep it from deteriorating. When changing refrigerate its not the refrigerate its the oil. There not compatible.

 

[American Locomotive]

I know I'm going to get some hate for this: But if you are the type of person who can tough it out if the AC breaks down, I'd recommend keeping your current system until it dies for good, and wait until the subsequent fall/cool season to replace it. I'm hearing A LOT of problems with newer systems and coil failures/leaks.

 

[bob smith1]

I know I'm going to get some hate for this: But if you are the type of person who can tough it out if the AC breaks down, I'd recommend keeping your current system until it dies for good, and wait until the subsequent fall/cool season to replace it. I'm hearing A LOT of problems with newer systems and coil failures/leaks.

I figured that was the plan unless there is drama going on.

 

[danski0224]

But if you are the type of person who can tough it out if the AC breaks down,

I have met a lot of people that claim to be this way, and then they pretty much immediately aren't when the magical cool box stops working.

 

[bob smith1]

deleted, TMI.

 

[danski0224]

Imagine being a guy that has not had normal AC for 6 years and in extreme cold, has frost on your blanket and floor, and no running water in extremes, yet HVAC licensed and serve others "need".....lol I swear it's odd but I fought to keep assets after a covid explosion, instead of being comfortable. My computers tap out before I do, so 85* sounds pretty good to me.....lmao.....

Good for you, you are in the top 0.5%... I would guess... as far as living without AC is concerned.

I have met several that claim to be close, but flip 180º when the AC breaks.

 

[bob smith1]

deleted, TMI...

 

[75gmck25]

Another option is to purchase one of the roll-around portable A/C units, preferably with dual hoses (usually a little more efficient). Use it now to cool your garage, and then move it into the bedroom or family room if you lose A/C and are waiting for repairs.

 

[jshillin]

I just had my upstairs unit replaced not long ago and I had them run a new line set. The extra cost was marginable and it made me feel better about it. My house is about the same size as yours and I have 2 units, 1 for upstairs and another for downstairs. The upstairs runs more in the summer and downstairs more in the winter. They are both inverters, so they run at low capacity most of the time. I have a 2 1/2 ton downstairs and 2 ton upstairs since the upstairs area is smaller than down.

 

[exmaxima1]

I just replaced the run capacitors for the second time, and added a "hard start" cap kit, so I think I will get a few more years out of my old Lennox. By then the newer R-454B systems (like Carrier Puron Advance) should be bug free.

 

[pcmeiners]

They claim it is normal to flush and reuse the lines.

Is there anything wrong with using the old lines?

Wonder how much oil will remain after a"professional" flushes a system, especially when many "professionals" do not produce leak free systems because it is time consuming.

 

[danski0224]

Wonder how much oil will remain after a"professional" flushes a system,

I have always felt that the risks from flushing a lineset outweigh the benefits of doing it.

especially when many "professionals" do not produce leak free systems because it is time consuming.

I've never had a customer pay for a pressure test on an existing lineset, nor have I ever had a customer want to replace a concealed lineset. What do you do? Replacing a lineset isn't always possible (not accounting for claimed cost issues).

There is a skill to brazing, and planning the installation to avoid putting that braze joint in a ****** location.

I've seen union pipefitters not purge with nitrogen on refrigeration piping jobs.

Unfortunately, corner cutting exists in many places, not just HVAC work.

 

[Ohmthis]

I know I'm going to get some hate for this: But if you are the type of person who can tough it out if the AC breaks down, I'd recommend keeping your current system until it dies for good, and wait until the subsequent fall/cool season to replace it. I'm hearing A LOT of problems with newer systems and coil failures/leaks.

Hearing from who? And who’s equipment? Every manufacturer has a turd, I’ve seen the learning curve of new equipment come and go. I may jinx myself, but I haven’t had any issues yet. Since these new refrigerants are so close the R410a, essentially the same coils and compressors are being used. It’s the flammability that has forced safety changes.

 

[PoorUB]

One more issue. My system is 3-ton and it honestly does the job though it runs quite a bit at times. The online calculators say I need 5 tons for my 3000ft2 2-story house. Would the same lines handle a 5-ton unit?

I'm jumping in a bit late, but if the existing 3 ton cools the home then that is all you need. It should run pretty much all the time in extreme heat. If it doesn't, it is too large.

I have had many customers want a larger system because the existing system runs a lot. If it maintains set point it is sized properly. In extreme heat, if it cycles a lot, 10 minutes on, 10 minutes off, it is to large for the house.

Also, most homes would be better with more insulation and weather stripping.

I was a bit surprised when we bought our home. I found out the existing homeowner had been on fuel assistance which explained the neatly new storm windows. What surprised was the tiny bit of insulation in the attic. There was 2-3 inches in most of it. There is 3 feet now! I would have thought that if fuel assistance was going to throw monat the house, insulating the attic would have been priority.

 

[pcmeiners]

I have always felt that the risks from flushing a lineset outweigh the benefits of doing it.

If I needed to do it I would purge it at least twice with an ample amount of cleaning agent.

If anyone wants a cheap flush, rather than close to $100.00......

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