Why doesn Sentry use an accumulator in the suction line?
An accumulator is a safety device, eliminating the possibility of liquid refrigerant traveling to the compressor. Sentry’s TCU is designed so it does not require an accumulator. The TCU uses a thermal expansion valve in conjunction with a crankcase pressure reducing valve. The combination adjusts refrigerant flow through the evaporator ensuring the refrigerant at the evaporator outlet is gas. The thermal expansion valve adjusts the flow of liquid refrigerant through the evaporator by holding the superheat constant. Superheat is the difference between the temperature at the evaporator outlet and the temperature implied by the refrigerant pressure at the evaporator outlet. Consistently superheating the refrigerant ensures the evaporator is never flooded. If the load decreases and the superheat falls, the TEV allows less liquid into the evaporator until the superheat climbs. Because of the “high” temperature in the evaporator the refrigerant pressure and temperature at the outlet of the e
