AGL_HA_ST_Discus_A2L_A1_EN_Rev00 19
4.6 Demand Cooling™
Liquid injection with "Demand Cooling™" can be used to extend application limits of 2D* and 3D*
compressors in low-temperature applications with refrigerants such as R448A, R449A, R407A and
R407F.
The Demand Cooling system uses modern electronics. A temperature sensor in the cylinder head
measures the discharge temperature and gives temperature signals to the Demand Cooling driver.
Once critical temperatures are reached, the driver energizes an injection valve which meters a
controlled amount of saturated liquid refrigerant into the compressor suction cavity to cool the suction
gas.
Demand Cooling is available as an optional compressor accessory. The Demand Cooling kit consists
of temperature sensor, electronic driver, electronic expansion valve, parts for tubing, filter-dryer, sight
glass and mounting bracket.
Figure 22: Injection parts on 2D* and 3D* compressors
Figure 23: Demand Cooling driver connections