Check Procedures; Temperature Sensor Check; Compressor Check - Lennox MCB Series Service Manual

5. Check Procedures

5.1. Temperature Sensor Check

Verify that power supplies have been disconnected to avoid electrick shock. Operate the system after restoring power and
the compressor and coil have had time to returned to normal operating temperature.
a. Disconnect the temperature sensor from the PCB (see Appendix D - Indoor/Outdoor Unit Disassembly).
b. Measure the resistance value of the sensor using a multimeter.
c. Check corresponding temperature sensor resistance value tables (see Appendix A - Temperature Resistance Values).

5.2. Compressor Check

a. Disconnect the compressor power cord from the outdoor PCB (see Appendix D - Indoor/Outdoor Unit Disassembly).
b. Measure the resistance value of each winding using a multimeter.
c. Check the resistance value of each winding in the following tables.
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