Hussmann HGM-1 BS, Installation & Operation Manual

Page: 19 / 70

P/N 0515297_E 3-3
HUSSMANN CORPORATION • BRIDGETON, MO 63044-2483 U.S.A.
HGM Merchandisers
• Rear connections:
– Case temperature sensor:
• Typically senses the temperature
of the air in the case.
Used by the controller to determine when
to power on or power off the compressor
or refrigeration.
– Compressor or refrigeration relay:
• Switches on the compressor or
refrigeration valve for cooling.
DISPLAY
The display includes three red LEDs and two
digits for temperature, defrost status, and error
codes.
The three display LEDs are red, and their
behavior matches the LEDs on the controller.
START-UP
Before applying power to the merchandiser,
remove the front grille.
Check thermostat knob is at the appropriate
position. See temperature adjustment on
Page 3-6.
Check the check the merchandiser’s cabinet
thoroughly for loose nuts and bolts. Check all
electrical connections. Inspect the refrigerant
lines for any visible damage or chafing.
Replace the front grille.
The following list of housekeeping practices
will assure trouble-free operation:
• Check operation of condenser fan motors.
Fan blades must turn freely.
• Check drain pan and heater to prevent
accidental overflow.
• Make sure doors are closing properly, and
that gaskets are sealed.
• Make sure all evaporator fan motors are
running. These can be seen through grille
inside of cabinet.
The optional evaporator fan remains
ON when the adjustment knob is in the
Off position.
Compressor
Powered On
Defrost Cycle
Temperature or
Sensor Alarm