A little background first. I service a lot of systems for a condo complex on the the Caribbean Sea, some condensing units are as close as 30 ft from the beach. Over the years I have been installing Carrier and then Arcoaire another Carrier product through ICP. It doesn't make any difference what brand Lennox, Rheem, etc, they all lose their fins and turn to powder within 3-4 years. Two years ago I started to replace the Carriers with Trane condensing units after changing out a Trane that was ten years old that someone else had installed. Overall the Trane held up well in the salty environment especially the fins since they used what I call the porcupine coil.
Here's my problem, the rotolock nuts are rusting out within 2 1/4 years and the compressors are rusting out from beneath the paint that Trane puts on within the same period. I replaced a compressor and rotolock nuts last week on another system and it seems the rotolock nuts are a cheap stamped out nut, whereas the old nuts from older Trane systems seemed to be a cast steel and a heavier metal. It's primarily the suction nuts. Has Trane gone cheap on these nuts?
Since I am having trouble with the Trane compressors rusting out whereas the Scrolls from Copeland in the Carriers didn't, I was curious to hear what other people think about changing from the Trane compressor to a Copeland scroll. The overall condition of the condensing unit is in good shape other than a little surface rust and will probably last 5 or more years.
I have 5 Trane condensing units side by side and they all are rusting out prematurely and I will have to look the customer in the eye and try and tell them that the older Trane's must have been better and I had no idea these things were going to fail so quickly. It sucks because I thought I was getting a good product.
PS I thoroughly coated the new rotolock nuts on the compressor replacement and LL Drier with auto undercoating, paint doesn't seem to work.