OPERATION:
CRANKCASE HEATER (HR1)
Compressors in all units are equipped with a 40 or 70 watt (depending on unit size) belly-band type crankcase heater. The heater prevents liquid from accumulating in the compressor. The heater is controlled by the crankcase heater thermostat.
CRANKCASE HEATER THERMOSTAT (S40)
Crankcase heater thermostat S40 controls the crankcase heater in all units and is located on the liquid line (see figure 2 for location).
1. When liquid line temperature drops below 50°F the thermostat closes which results in the heater being energized.
2. When liquid line temperature rises above 70°F the thermostat opens which results in the heater being de-energized.
CHECKOUT:
Belly-Band Crankcase Heater: Using meter set on ohms, check crankcase heater resistance. If resistance is 0 ohms or infinite, replace the crankcase heater.
Crankcase Heater Thermostat: As the detected temperature changes, the resistance across the sensor changes. Table 15 on page 68 shows how the resistance varies as the temperature changes for this sensor.
NOTE – When checking the ohms across a sensor, be aware that a sensor showing a resistance value that is not within the range shown in table 15 on page 68, may be performing as designed. However, if a shorted or open circuit is detected, the sensor is faulty; the sensor needs to be replaced.
STATUS CODE:
None
ERROR CODES:
None
