R504 Alternative?

[TracyDJMan]

Hello, I’ve got an old Hobart machine that the client wants to get going. It’s quite beat up but gets cold. I didn’t chuck my gauges on it and it’s in pieces so I don’t know if it will get down to temp, but concerned that if it is low we won’t be able to get 504. This is a 2 door stand up freezer. What is a good “drop in” for 504? If not a drop in, what other options? No tags indicating a retrofit. Thanks so much!

[chemi-cool]

Never heard of 504.
Could it be 502?
You can retrofit 502 with 438A without changing type of oil.

[TracyDJMan]

Never heard of 504.
Could it be 502?
You can retrofit 502 with 438A without changing type of oil.

It was 502, I misread. 438A is a good option? Okay thank you!