Options and Accessories 169Service Manual – SW8000Thermostat (S33)(Refer to Figure 11)Note: The Thermostat is located inside the Evaporator-Heater Unit in the cab.1. Remove the top cover/nozzle assembly from the Evaporator-Heater Unit.2. Remove the front panel from the Evaporator-Heater Unit.3. Remove the two electrical connectors (BLK/WHT and GRN wires) from the Thermostat and check thecontinuity across the two terminals.Note: The Thermostat is normally closed and should have continuity across the terminals atambient temperatures above 31° F.• If there is continuity across the terminals, the Thermostat is working correctly.• If there is very high resistance or no continuity across the terminals, replace the Thermostat.Service Note: To verify that the thermostat is operating correctly, spray electronic componentcooler or canned air dusting spray onto the probe embedded in the evaporator coilsto cool the probe to below 31° F.• The Thermostat should open and you should read an open circuit through the terminals with the probebelow 31° F.• Once the probe warms up to 39.5° F, there should again be continuity through the Thermostatterminals.
