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LGT/LCT036, 048, 060, 072
Cooling Operation
A-Two-Stage Thermostat
1-Economizer With Outdoor Air Suitable
Y1 Demand -
Compressor Off
Blower Low
Dampers Modulate
Y2 Demand -
Compressor Low
Blower High
Dampers Full Open
Note - Compressor is energized after damper has been
at full open for three minutes.
2-No Economizer or Outdoor Air Not Suitable
Y1 Demand -
Compressor Low
Blower Low
Dampers Minimum Position
Y2 Demand -
Compressor High
Blower High
Dampers Minimum Position
B-Three-Stage Thermostat OR Room Sensor
1-Economizer With Outdoor Air Suitable
Y1 Demand -
Compressors Off
Blower Low
Dampers Modulate
Y2 Demand -
Compressor Low
Blower High
Dampers Full Open
Note - Compressor is energized after damper has been
at full open for three minutes.
Y3 Demand -
Compressor High
Blower High
Dampers Full Open
2-No Economizer or Outdoor Air Not Suitable
Y1 Demand -
Compressor Low
Blower Low
Dampers Minimum Position
Y2 Demand -
Compressor High
Blower High
Dampers Minimum Position
Y3 Demand -
Compressor High
Blower High
Dampers Minimum Position
High Speed Compressor Cooling Operation:
RTU MENU > COMPONENT TEST > COOLING > COOLING
STAGE 2
Low Speed Compressor Operation
RTU MENU > COMPONENT TEST > COOLING > COOLING
STAGE 1