Refrigeration oils must be miscible with the system refrigerant because:
A) The system depends on the refrigerant to carry the oil throughout the system to lubricate all the refrigeration components.
B) The compressor cannot operate properly without liquid refrigerant in the crankcase.
C) The system depends on the refrigerant to return the oil to the compressor.
D) The system depends on the oil to return the refrigerant to the compressor.
Question 2
Automatic expansion valves are similar in operating concept to:
A) Manual valves. B) Electronic expansion valves.
C) Fixed restrictions. D) Pressure regulators.
The tracheal system of insects.
Anatomical Charts Digestive System
Four methods of recording electrical activity of the nervous system.
Effects of the Autonomic Nervous System
The Digestive System "الجهاز الهضمي"
Development of the Nervous System: Transverse section