Trane RAUC-C50 Air Conditioner User Manual


 
SS-SVX09A-EN 77
System Pre-Start Procedures
Chilled Water Sensor Checkout (Honeywell Sensor)
ƽ WARNING
Hazardous Voltage!
Disconnect all electric power, including remote disconnects before servicing. Follow proper
lockout/tagout procedures to ensure the power can not be inadvertently energized. Failure to
disconnect power before servicing could result in death or serious injury.
1. Verify that the main power disconnect switch and the control circuit switch 1S2, in the unit
control panel, is “OFF”.
2. At the temperature controller, disconnect the wire connected to terminal T1. Use a digital
ohmmeter to measure the resistance across terminal T and the wire removed from terminal T1.
3. Use the conversion chart in Figure 37 to convert the measured resistance to an equivalent
temperature.
4. Measure the actual temperature at the sensor location. If the measured resistance in step 2 is
not within ± 10.0 ohms of the actual temperature, the sensor is out of range; replace it.
Note: Before condemning the sensor, verify that the connecting cable resistance is not excessive.
Refer to the “Field Installed Control Wiring” section.
5. Make all necessary repairs and reconnect the duct sensor lead to terminal T1 on the controller.
6. Turn all control switches to the “ON” position and restore power to the system.
Figure 38. W7100G Chilled Water Controller