Abstract: An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

Abstract: A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

Abstract: Apparatus and a method for providing an electrical circuit to protect the internal components of a dual source combination motor-generator refrigeration unit having an internal power source and an external power source. The circuit is comprised of switching apparatus, a voltage sensitive relay, a high pressure switch, a time delay relay, an electrically operated clutch, a speed control solenoid and other electrical components to protect the engine, motor-generator, vapor compression refrigeration system and the electrical components sensitive to voltage fluctuations from various malfunctions including loss of engine speed, high refrigerant pressure, voltage fluctuations and operation of the compressor in an improper mode.