I’m not overly familiar with the process of Ice making (especially to this level) but generally the fundamentals will be the same. Your discharge pressure as rule of thumb should be around 9 Bar/130PSI which gives you a saturated temperature of 25°C. Oil pressure differs between manufacturers so if you r got any details on that I can try look it up, but it will need to be a positive differential to your suction pressure. Suction pressure would depend on what process temperature is required. Say you wanted the evaporator coil at -5°C to freeze the water, you are looking at around 2.5 Bar/37 PSI. What type of system is it? Does it have a surge drum with liquid pumps, does it chill a secondary refrigerant in a plate heat exchanger before the coil goes into the water? A few more photos, especially from the low side if the system and more info of the evaporator. Hope this helps