Trane RAUC-C60, RAUC-C50 manual Economizer Actuator Checkout, Zone or Discharge Air Temp Controller

System Pre-Start Procedures

Discharge Air Sensor Checkout (Honeywell Sensor)

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 Discharge Air Controller, in the unit control panel, 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.Restore power to the system and turn all control switches to the “ON” position.

Economizer Actuator Checkout

(w/ “Zone” or “Discharge Air” Temp Controller)

The following procedures should be used to verify that the field provided economizer actuator(s) function properly. These procedures are based on using a typical Honeywell actuator. If another type actuator is used, refer to the specific checkout procedures for that actuator.

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.Turn all control switches to the “Off” position to deactivate the Evaporator Fan and the Mechanical Cooling. Verify that the main power disconnect switch for the condensing unit and the control circuit switch 1S2, in the unit control panel, is “OFF”.

2.Verify that the field provided disconnect switch and/or the control circuit switch for the economizer actuator(s) is “OFF”.

3.At the actuator, disconnect the control wires connected to Terminals W, R, B, and Y.

4.Install a jumper across the actuator terminals R-to-W-to-B.

5.Close the field provided disconnect switch and/or the control circuit switch for the economizer actuator(s). If the economizer actuator is working properly, it should drive to mid-position.

6.Open the field provided disconnect switch and/or the control circuit switch for the economizer actuator(s) and remove the jumpers installed in step 4.

7.Reconnect the control wires to the actuator terminals W, R, B, and Y.

8.Restore power to the actuator circuit and turn all control switches to the “ON” position and restore power to the system.

74 SS-SVX09A-EN