Which limitation arises when an ammonia-based refrigeration evaporator operates below its minimum design temperature?

💡 Explanation

When an ammonia evaporator operates below its minimum temperature, excessive amounts of refrigerant condense in the evaporator and return to the compressor because ammonia's vapor pressure dramatically decreases when cold which dilutes the compressor lubricant. Therefore lubricant breakdown results, unlike frost, refrigerant decomposition or valve blockage, which, although related to temperature, are triggered by separate mechanisms.

• Which outcome is most likely when a positive displacement pump's outlet valve is inadvertently closed during operation?
• Which risk increases when a CNC lathe's servomotor overheats?
• Which failure is accelerated in a diode subjected to high reverse voltage?
• Which risk increases when setting extremely tight tolerances in CNC machining?
• Which mechanism minimizes torsional vibration in a diesel engine's crankshaft?
• Which outcome occurs when an aircraft aileron servo jams at high speed?