2-2
evaporator fan motors continue to run to circulate air
throughout the container.
When the return air temperature increases to 0.2
_
C
(0.4
_
F) above set point, and providing a sufficient off time
period has elapsed, relays TC and TN energizes to restart
the compressor and condenser fan motor. Also, at this
time,the cool light is illuminated.
= 18 Volt Energized Circuit
CONTROL TRANSFORMER
= 24 Volt Energized Circuit
= De-energized Circuit
Figure 2-1. Cooling
2.4.3 Controller Set ABOVE ---10
_
C (+14
_
F)
or ---5
_
C (+23
_
F) optionally
NOTE
Setting the controller above ---10
_
C
(+14
_
F) or ---5
_
C (+23
_
F) optionally on
units with two-speed motors will place the
motors in high speed. (Contactor EF
energized)
a
.
Cooling (See Figure 2-1.
)
With decreasing supply air temperature and if the
supply air is above set point, the unit will be cooling with
the condenser fan motor, compressor motor and
evaporator fan motors energized. Also, at this time, the
cool light is illuminated.
When the air temperature decreases to a tolerance
above set point, relay TI energizes and the in-range light
is illuminated. (Refer to section 1.12.5, Code 30).
If the air temperature continues to fall, modulating
cooling starts at approximately 2.5
_
C (4.5
_
F) above set
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