Electrical, Refrigeration and
µ
P-D Menu Flow Diagrams
Refrigeration Schematic: Full Cool
9-38
CRR-20 & CRR-40, September 1999
Flow and Pressure Diagram
CRR-20 & CRR-40
Full Cool
1.
3DS Compressor
Compressor operation has a variable delay on initial start-up when the
unit shifts to a cooling mode requiring the compressor to start.
4.
Condenser Fan Pressure Switch (CFPS)
Is a normally CLOSED switch.
It OPENS at 1380 +/- 50 kPa, 13.8 +/- 0.5 bar, 200 +/- 7 psig.
It CLOSES at 1100 +/- 50 kPa, 11.0 +/- 0.5 bar, 160 +/- 7 psig.
5.
High Pressure Cutout Switch (HPCO)
Is a normally CLOSED switch.
It OPENS* at 2410 +/- 70 kPa, 24.1 +/- 0.7 bar, 350 +/- 10 psig.
It CLOSES** at 1655 +/- 70 kPa, 16.5 +/- 0.7 bar, 240 +/- 10 psig.
*CRR-20-63: 2240 +/- 70 kPa, 22.4 +/- 0.7 bar, 325 +/- 10 psig.
**CRR-20-63: at 1590 +/- 70 kPa, 15.9 +/- 0.7 bar, 230 +/- 10 psig.
9.
High Pressure Relief (Fusible Plug)
BLOWS at 100 C (212 F).
29.
Controller (
µµ
P-D)
Thermoguard (
µ
P-D) with digital thermostat, thermometer and fault
indicator monitor.
Null Mode Operation
During the Null mode, the compressor does not operate. If the con-
denser fan is ON (based on condensing pressure) when the unit shifts
to Null, the condenser fan operates for 30 seconds and stops.
Evaporator fans continue to operate (evaporator fan speed is deter-
mined by return air temperature and economy mode setting).
37.
Water Pressure Switch (WPS) (Option)
Is a normally CLOSED switch.
It OPENS at 117 +/- 21 kPa, 1.17 +/- 0.21 bar, 17 +/- 3 psig.
It CLOSES at 35 +/- 21 kPa, 0.35 +/- 0.21 bar, 5 +/- 3 psig.
40.
High Pressure Relief Valve (Before 8/99)
OPENS at 3450 +345/-105 kPa, 34.5 +3.5/-1.0 bar, 500 +50/-15 psig.
CLOSES at 2760 kPa, 27.6 bar, 400 psig.
Fusible Plug on Tank (After 8/99)
BLOWS at 100 C (212 F).
High pressure gas
High pressure liquid
Low pressure gas
Low pressure liquid
Condensing high pressure gas
Low pressure vaporizing liquid
Liquid refrigerant injection
Содержание CRR-20
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