Temperature Thermistor Sensors - Lennox LGT156H Installation Instructions Manual

240 & 300
Condenser fans 1, 2, and 3 are energized when
compressor 1 or 2 are energized. As cooling demand
increases, all six condenser fans are energized. See
figure 24.
Condenser fans 1, 2, 4, and 5 are de-energized when
outdoor temperature drops below 62°F (17°C).
Condenser fans 3 & 6 modulate to maintain target
liquid temperatures when outdoor temperature drops
below 62°F (17°C).
240 & 300 CONDENSER FANS
COMPRESSORS
1 2 3 4
FIGURE 24
COND.
COND.
FAN 4
FAN 1
COND. COND.
FAN 5 FAN 2
COND. COND.
FAN 6 FAN 3
Page 51
Prognostic Sensors
Temperature thermistor sensors (RT46-53) are located
on specific points for each refrigeration circuit.
Temperature thermistors
temperature input to the unit controller for proper cooling
operation as well as system protection. Controller logic
will de-energize compressors for each refrigeration circuit
when evaporator coil temperature falls below 32°F (0°C)
to prevent evaporator freeze-up.
Each thermistor must be specifically placed for proper
unit operation and to initiate valid alarms. See table
14-16 for proper locations.
TABLE 14
LGT/LCT156
Cat. No. Ass'y. No.
22J06 623049-01
23V50 623049-05
TABLE 15
LGT/LCT180
Cat. No. Ass'y. No.
22J06 623049-01
23V50 623049-05
TABLE 16
LGT/LCT210, 240, 300
Cat. No. Ass'y. No.
22J06 623049-01
23V50 623049-05
provide continuous
Sensor
Figure
Yellow, Blue
RT46, 47 25
RT48, 49 26
Sensor
Figure
Yellow, Blue, Red
RT46, 47, 50 27
RT48, 49, 52 28
Sensor
Figure
Yel, Blu, Red, Grn
RT46, 47, 50, 51 29
RT48, 49, 52, 53 30
508288-01 9/2022