Hello,

I am currently on a ship running a chilled water system using 5 hermetic Copeland ZR19 compressors. A couple of years ago the refrigerant got changed from R22 to 417A. The system is about 10 years old and in the last couple of years we have changed out 3 of the 5 compressors due to high hours. Last compressor was done about a year ago and then we also had the 2 heat exchangers replaced and cleaned the pipework.
Now when leaving a shipyard last month this compressor shows a fault and stopped running. On Inspection I found that when reset it would run for about 1 minute but releasing the internal pressure valve constantly (Not even close to reaching high pressure trip) until going into fault mode. I removed the filter for inspection and found that it seemed to be full of oil.
I had a couple of days in port where I after much effort finally got a refrigerant engineer to come have a look at the system. He deemed the compressor dead, luckily I carried a spare so I got him to install the new one. After installation of the new compressor the exact same thing happened with the internal release. The refrigerant engineer told me that his believe was that there was a oil lock in the system. Unfortunately we did not have time for him to do more investigation.

Now when I looked on the Copeland website for some support I came across an article stating that Copeland does not support the 417A due to unknown oil separating capabilities and recommends 407C as the R-22 replacement.

Now my question is, do you believe the 417A has caused the grief with the compressor?
And what will I need to change in my system if I decide to go with the Copeland recommendations?
Can anyone give me any recommendations on where to move from here?

Thanks,
Jauma