Interesting that you have a F18SC. But I do not find a 85 inch unit. F18 is the model series, SC means it is a refrigerated salad top with pans. 60 is the long one with one 19 inch door and one 27 inch door. If you have 3 doors, it would be either a 79 with one 19″ and 2 27″ doors or a 87 with three 27 inch doors.. My books date from 2013, so they may have started making longer ones. Since they are now Welbuilt instead of Maitowoc, manuals have gotten harder to get and the F18 is now migrating to the 4400 series.
Regardless, one has to understand that Delfield is more like a walk in than most small units. They use suction pressure control for the condenser with a solenoid valve that is temp controlled. The temp controller is here Temp control .
The suction pressure control should be set 55psi cut in and 30 cut out for R404. The temp control 2.5 to start. The top rail has it’s own solenoid valve and separate from the evaporator inside. Be aware that the controller cycles the evaporator fans on and off every 3 minutes during the non cooling cycle.
If you give us a call at 800-438-8898, our parts identification specialists can give you a hand, but they will definitely need your serial number on the unit. Delfield made a lot of customized units, so they aren’t as open giving details for which part you need without a serial number.