Crankcase Heater, Checkout And Status / Error Codes; Belly-Band Crankcase Heater Thermostat; Checking Belly-Band Crankcase Heater - Lennox XP25-024-230-01 Installation And Service Procedure

Crankcase Heater, Checkout and Status / Error Codes

OPERATION:
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 controls the crankcase heater in all units and is located on the liquid line (see figure 2 on
page 6 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.
Crankcase Heater Thermostat
CHECKOUT:
Belly-Band Crankcase Heater:
infinite, replace the crankcase heater.
CRANKCASE HEATER (HR1)
CRANKCASE HEATER THERMOSTAT (S40)
Figure 41. Belly-Band Crankcase Heater Thermostat
Using meter set on ohms, check crankcase heater resistance. If resistance is 0 ohms or
Figure 42. Checking Belly-Band Crankcase Heater
Page 64
Belly-Band Crankcase Heater - 240VAC, Watts
40 or 70
XP25