Heatcraft Refrigeration Products PRO3 Benutzerhandbuch

PRO

3

 Side Mount Packaged Refrigeration System Installation and Operations Manual, May 008 

 

 7

1.  Refer to all local codes for proper connection. 
.  A knock-out is provided for 1" conduit on the side of the 

condensing unit section above the electrical box. See FIGURE 12.

3.  Wire will be brought into the electrical box through the 

bottom of the electrical box and connected to the top of the 
contactor.

1.  Power is provided to the temperature control, compressor 

contactor and cooler evaporator fans.

.  The temperature controller closes and energizes the 

compressor contactor, starting the compressor, evaporator 
and condenser fan(s).

3.  When the system reaches the desired box temperature, the 

temperature control will de-energize the compressor contactor. 
Evaporator fans will continue to operate at this point. 

4.  When the fixture temperature rises above the set point  

and minimum off-time has elapsed, the temperature control 
will close and re-energize the compressor contactor.

Air defrost units are pre-programmed for 4 defrost per day. These 
periods  are  reprogrammable.  When  the  coil  temperature  reaches 
38°F, the control will terminate the defrost cycle. 
For programming information see pages 7-16.

PRO

3 

packaged refrigeration system cooler with electric defrost and 

freezer units come factory equipped with an electronic temperature/
defrost control. 
For programming information see pages 7-16.

Power  is  provided  to  the  temperature  control  and  compressor 
contactor.  The drain line heater as well as the crankcase heaters will 
also have continuous power supplied to them.
The  temperature  controller  energizes  the  compressor  contactor, 
starting the compressor and condenser fan(s).  The evaporator fans 
will be energized by the electronic controller.
When  the  system  reaches  the  desired  box  temperature,  the 
temperature control will de-energize the compressor contactor and 
the evaporator fans. 
When the temperature rises above the set point and minimum off-
time (4 minutes) has elapsed, the temperature control will close and 
re-energize the compressor contactor.
1.  During normal operation, at the preset times of day, the 

temperature/defrost control will de-energize the compressor 
contactor and evaporator fans and energize the defrost 
heaters. These functions are controlled through relays on the 
controller.

.  When the coil has defrosted fully and has reached the  preset 

coil temperature (as sensed by the coil  temperature sensor) 
the defrost heater de-energizes and the fan delay and drip 
sequences begin.

3.  The temperature/defrost control energizes the compressor 

contactor, starting the compressor and condenser fan(s).

4.  Freezer evaporator fans will be energized by the temperature/

defrost control when the coil temperature reaches 35°F or fan 
delay time has elapsed.

Cooler: 35˚ F

Every 3 hours of  

compressor run time

60

–

–

38˚ F

Cooler w/ Electric 

Defrost:  34˚ F

40

65˚ F

Freezer: -10˚ F

4 times / day

40

65˚ F