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Other than pressure switch settings and oil charge, is there any reason you can not use R-22 in R410A condensing unit with R-22 evap coils? 25 ton coils are expensive to change unless totally NECESSARY. Manufacturers are using the CYA argument. Is it legitimate? Thanks
 

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Since there is a HUGE difference in capacity between the two refrigerants, I'm going to say that it won't work well.

The oil would be a non-issue as POE is compatible with all types of refrigerant, that isn't an issue.
 

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Many contractors are experiencing compressor burnout problems with R-410A HVACR systems soon after they're converted from R-22 refrigerant.
 

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i would say that the condensing coil would be different in the capacity and if you are using the same compressor there might or there is a difference in the pumping ratio in the compressors but i could be wrong on this.
 

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BTU for BTU, an R22 compressor moves more refrigerant then an R410A compressor. So using R22 in a R410A condenser, will lower its capacity.
 

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What do you think the problem may be? Any ideas?
Some possible causes.

Didn't blow out the line set if they reused it, and left too much min oil in the system.

Reused old indoor coil and didn't blow it out, or its mismatched to the condenser.

Didn't pull a low enough vacuum, which left too much moisture in the system.

Poor brazing technique. Causing leak problems and running system in a vacuum drawing air and moisture into the system, then pumping the remaining charge into the condenser when to fix the leak, which means only pulling a vacuum on the line set and coil, leaving moisture in the charge that has been pumped back into the condenser, causing an acid burn out later.

Often, the LLFD isn't changed when the leak is at a braze joint outside of the condenser. A few minutes saved along with a few dollars for the LLFD that wold ahve to be replaced under warranty. And you end up a problem that is wrongfully blamed on R410A.
 

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Mismatching equipment

R410a requires much less compressor horsepower per ton then R22 due to running with a higher compression ratio .So running R22 in a R410a compressor could cause over amping even with a low head and high suction potential High superheat and ultimately burn the compressor another problem may be oil return. Would not recommend this practice. If it was meant to run on R22 , R407C Etc it would have a alternate rating on it.
 

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R410a requires much less compressor horsepower per ton then R22 due to running with a higher compression ratio .So running R22 in a R410a compressor could cause over amping even with a low head and high suction potential High superheat and ultimately burn the compressor another problem may be oil return. Would not recommend this practice. If it was meant to run on R22 , R407C Etc it would have a alternate rating on it.
If it had a higher compression ratio, then it would take more horse power.
 

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R22 in new 410 Air handler?

Hello,

A month ago I had a company install a new Carrier PA13NR060 compressor unit with R22 wO my old air handler. Worked well for a month or so, and the air handler or copper lines are now leaking. Probably did for a while, which caused the compressor to fail eventually.

Anyway, just had a new air handler installed today, Carrier FV4CNB006. The specs say that is a PURON only unit. They haven't charged the system yet, but will by tomorrow afternoon, and they plan to use R22.

From what I can tell from this forum is that R22 is less pressure than 410 so that shouldn't be an issue. And the oil is not compatible,but since the air handler hasn't been charged, that shouldn't be an issue either.

Should I be concerned at all? Thanks!

PS.Can you confirm the tonnage of these units from the model numbers above?
 

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The new air handler's coil's TXV will need changed out to an r22 TXV. the outdoor is a 5 ton, and as far as I know the air handler can be used on a 5 ton. Carrier stopped putting tonnage number on air handlers quite some time ago.
 

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Converting AHU from 410 to 22

The only mechanical issue will be the metering device. It would be imperative to use a T.E.V. and not a fixed metering device or "Piston" to achieve proper or specified efficiencies from said system, as well as maintain any A.R.I. matching possibility. I would be concerned, however, about the contractor who installed an R22 condenser on an air handler that was in poor shape and leaking. Obviously permits were NOT obtained (Federal D.O.E. legislation has eliminated condenser slapping any system, unless it is A.R.I. certified, ALL municipalities are required to obtain these A.R.I. #s prior to permit issuance) and an incomplete diagnosis was performed. At this point they are performing the 2nd installation at your home without obtaining a permit. I hope the $ saved and gamble on your part is worth the risk, potential fines and legal exposure you have put yourself in
 

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Obviously permits were NOT obtained (Federal D.O.E. legislation has eliminated condenser slapping any system, unless it is A.R.I. certified, ALL municipalities are required to obtain these A.R.I. #s prior to permit issuance) and an incomplete diagnosis was performed.

Whats the reg number from the DOE that prohibits this.

Condensers are considered a "part" not a system.
 

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D.O.E. Regulations

http://www1.eere.energy.gov/buildings/appliance_standards/pdfs/cacfurn_dfr.pdf

This link is good material to read when you need sleep. LOL. There are some very interesting facts in this document including recomendations of evaporative coolers being installed on air cooled condensers to acheive better condensing temps (we have done this in a few instances, although unintended consequences such as mold and mildew buildup on and around condenser)

The only way to ensure these effeciency ratings is through the A.R.I. test data and subsequent rating #. Any municipality issuing permits without these #s are not enforcing these standards.

We work in 20+ municipalities (city and county) here in Florida and every permit pulled in the last 5 months has required the A.R.I.#s. On several occasions we have lost jobs to companies that are willing to circumvent the rules of engagement.

In addition the minimum effeciency standards for the southeast region will increase from 13 seer to 14 seer. This was originally slated to take effect on March 15 2013, but I recently read an article stating March 1 2015 so I am not positive the roll out date on the new minimum effeciencies for the southeast region.

In retrospect, I suppose some states or municipalities (outside of Florida) would not implement measures to ensure enforcement of new stringent regulations.

In Florida changing either indoor or outdoor unit or both require permits. Again I presume other states reciprocate that perspective. It seems the only alteration you can perform without a permit in this state is open a window or door. LOL
 

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In many areas here, i don't need to pull a permit to change out an air handler and condenser, let alone if I'm only changing out a condenser.
 
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