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IDX-OM-Y002
Chapter 7
Documents
IDF60/70/80/90 Series
7.5
Air and refrigerant circuits and functions
7-7
Air circuit
The humid hot air that enters the air dryer first goes into the reheater, and exchanges its heat with
dehumidified cold air to pre-cool it. Then, the air enters the evaporator, where it releases its heat to
a cold HFC, and is dehumidified and cooled further to let moisture separate. Finally, the air
exchanges heat with the hot air coming to the air dryer and its temperature increases higher, and it
leaved the air dryer as warm, dry air.
Refrigerant circuit
The fluorocarbon gas in the refrigerant circuit is compressed by the compressor and cooled by the
water-cooled type condenser to become liquid. When passing through the capillary tube or the
thermostatic expansion valve, the HFC gas is regulated and its temperature decreases. While
passing through the cooler part, it evaporates rapidly, taking the heat from the compressed air,
and is sucked in by the compressor. The volume control valve opens when the compressed air
has been cooled sufficiently, and prevents condensed water from being frozen by excessive
cooling.
Coolant water circuit
Automatic water supply valve are installed in the cooling water inlet side of the water-cooled
condenser. The valve by appropriately controlling the cooling water in response to variations in
load, and serves to maintain the condensing pressure constant. At the time of product shipment, it
is set as the condensing pressure in the no-load operation state becomes a value in the table
below. In addition, it is normal if the range is operating during the condensation pressure in the
table below.
Models
Condensing pressure set
point
Range of driving of normal
condensing pressure
IDF190D-3-W
IDF240D-3-W
1.7 +/- 0.1 MPa
1.5 to 1.9 MPa