R-12 to R-134 change

[Blue Stocking]

Help from wiser heads please. Water cooled Adler Barbour heat exchanger failed and salt watered the evaporator as well. Have new pre-charged R-12 unit would like to use with new R-134 compressor (air-cooled this time). Any problem evacuating the R-12 and replacing with 134? Thanks.

[Stu Jackson]

Don't think it will work, but ask Richard Kollman

[sailorchic34]

The properties of 134A is similar but not exactly the same as R12. It will work, provided you also change out the oils too, as the oils are not compatible between the two. You will lose a bit in efficiency too, meaning the compressor will run a bit more to cool the box.

[a64pilot]

Originally Posted by sailorchic34

The properties of 134A is similar but not exactly the same as R12. It will work, provided you also change out the oils too, as the oils are not compatible between the two. You will lose a bit in efficiency too, meaning the compressor will run a bit more to cool the box.

Seals as well maybe? Trying to remember as its been a long time since I did a conversion, but I want to think we had to change seals, and there was a color difference that made one obvious from the other?

Oh and to be legal and environmentally friendly, you have to recover the 12, heck of a fine if you don't and get caught.

[deluxe68]

I would just change everything as long as you are replacing the compressor. I have a CFC cert but do not work on the equipment enough to know about every configuration. Generally, small compressors already come pre-loaded with refrigerant. You may have to flush the existing piping, connect the new parts, evacuate the piping, then open the valves from the compressor to allow gas to circulate. Not sure what unit you are talking about that is pre-charged? I did not think that the evap would be pre-charged.

[sailorchic34]

Originally Posted by a64pilot

Seals as well maybe? Trying to remember as its been a long time since I did a conversion, but I want to think we had to change seals, and there was a color difference that made one obvious from the other?

Oh and to be legal and environmentally friendly, you have to recover the 12, heck of a fine if you don't and get caught.

Oh right you are. Seal where piping is jointed by threaded connections might need to be changed too. Odd that the new compressor would be pre-charged with R12. No one really uses that anymore due to ozone depletion of which R-12 is right at the top, least in the US and EU.

[Blue Stocking]

This would be a new pre-charged compressor unit with r134. Evaporator is new, never used, been on the shelf a few years. Old compressor froze up from salt water ingestion, not sure if salt water polluted up to the capillary tube on the old evaporator. Evaporator has Quick-connects, think I could purge it of r12, and add correct amount of r134 once the 2 components are connected.