Heatcraft Refrigeration Products H-IM-79B User Manual

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8
CU
M
M
 = Master Evaporator
CU
= Condensing unit
Start-Up Operation
SINGLE SYSTEM with 1 EVAPORATOR
• Check all wiring connections to be sure they are correct and tight.
• On condensing unit
- Check the setting of Time Delay relay. It should be set at 1 minute (the
second marker).
- Check the Low Pressure switch setting on freezer units. It must be set to 0
PSIG cutout, 10 PSIG cut-in to allow positive start and operation, especially
in cold ambients. This can be changed to a higher value in warmer climates.
On cooler units, the Low Pressure switch has a fixed setting and cannot be
adjusted.
• Turn power on
• On the evaporator
- Use the “PROGRAM REVIEW” button to scroll through settings.
- Check “
rEF
” (Refrigerant Type). Factory defaults are: Air Defrost R-22,
Electric Defrost R-404A. Change to the refrigerant being used.
- Check 
“bot”
 (Box Temperature). Factory defaults are: air defrost 35°F and
electric defrost –10°F. Change to the desired temperature.
- Review and change other setting if necessary
- See procedures below on how to change settings.
Start-Up Operation