Heatcraft Refrigeration Products H-IM-79B - Manual (Page 11)

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INITIAL POWER ON
At the initial application of power to the system, the compressor and the evaporator fans
will be in a 4 minute hold-off cycle and will not start immediately. When there is a call for
COOLING, the expansion valve (EEV) opens, then the compressor is started. The
compressor will then run for a minimum of 2 minutes in the “hold-on” cycle. (This means
that the compressor will run for a minimum of 2 minutes before shutting off even if the box
temperature is met.)
The LED alternately displays BOX TEMPERATURE and MODE of operation. On a call for
cooling, dLY will show while the expansion valve is opening. After the compressor starts
the LED will alternately display BOX TEMPERATURE and Coo .
On multiple evaporator systems the MASTER evaporator will display BOX
TEMPERATURE and Coo . The SLAVE evaporators will display Coo only.
When the room thermostat setting is satisfied, and if the compressor ran for at least 2
minutes, the EEV will close and the compressor will pumpdown and shut off. The
evaporator fans will continue to run. The LED will alternately display
oFF and BOX
TEMPERATURE.
When the room sensor detects a rise in temperature of approximately 2°F, and the
compressor has been off for at least 4 minutes, the EEV will open to its last position then
the compressor will start. The valve is then adjusted as necessary to obtain the setpoint
superheat setting. During this time, the compressor will run for a minimum 2 minutes “hold-
on” cycle.
The four minute “Hold-off” can be bypassed and the system started immediately by
pressing the “Reset” button on the Beacon II board.
OPERATING MODE DISPLAY
oFF - Off
Coo - Cooling
Pdn - Pumpdown
dEF - Defrost
drn - Draining
dLY - Delay
tSt - Test
SEr - Service
Start-Up Operation