Compressor change out data?

[jrc2905]

What information do I need to swap out a compressor on a refrigeration unit? I have an older reach in cooler designed for R-12. I realize I need to convert the refrigerant also.
What I am asking is what data do I need from the existing system to order a replacement compressor. This may be second nature to some techs but I have only done new installs, which come as a package unit. I also want to offer compressor change outs to customers who have 10-seer residential cooling and do not want to or cannot afford a complete change over to a 13-seer unit. The counter people at the supply house are of no use. One supply house I contacted said he just needs to know the BTUs of the unit. Sounded too simple to me. I was under the impression compressor ratios do matter. I cannot locate any reference material on this subject. Is there any good reading material on this subject

[k-fridge]

Many of those old R-12 compressors are still in production, if so the best thing to do is to get the same one. If not, any good supply house should be able to cross fom the compressor number. BTU rating is relative to temperature range so you need more than that to cross.

As for refrigerant, there's lots of blends that work well in medium temp applications. MP-39, R-409 are two of the better ones. R-416 also works well and some people who don't know better use HotShot. :D

[jrc2905]

So what would I be looking for Model # on the compressor?

[k-fridge]

So what would I be looking for Model # on the compressor?
Should be on a plate. If it's a Tecumseh use the numbers to the right of the second line. EX: AE 4440 A. Most of the small Tecumseh's are still available.

Just write them all down and call the supply house, if they are any count they can cross it.

[jrc2905]

thanks

[k-fridge]

thanks

Anytime

[the mojo]

The quote of the day from K.:D And for some people who don't know better use Hot Shot.:D Total agreement on that.