Carrier 48TC*D08 Wiring Diagrams, DCV Minimum and Maximum Position, Supply-Air Sensor Input

48TC

5.Turn the DCV setpoint potentiometer CW until the DCV LED turns off. The DCV LED should turn off when the potentiometer is approximately 9-v. The actuator should drive fully closed.

6.Turn the DCV and Exhaust potentiometers CCW until the Exhaust LED turns on. The exhaust contacts will close 30 to 120 seconds after the Exhaust LED turns on.

7.Return EconoMi$er IV settings and wiring to normal after completing troubleshooting.

DCV Minimum and Maximum Position

To check the DCV minimum and maximum position:

1.Make sure EconoMi$er IV preparation procedure has been performed.

2.Connect a 9-v battery to AQ (positive node) and AQ1 (negative node). The DCV LED should turn on. The actuator should drive to between 90 and 95% open.

3.Turn the DCV Maximum Position potentiometer to midpoint. The actuator should drive to between 20 and 80% open.

4.Turn the DCV Maximum Position potentiometer to fully CCW. The actuator should drive fully closed.

5.Turn the Minimum Position potentiometer to midpoint. The actuator should drive to between 20 and 80% open.

6.Turn the Minimum Position Potentiometer fully CW. The actuator should drive fully open.

7.Remove the jumper from TR and N. The actuator should drive fully closed.

8.Return EconoMi$er IV settings and wiring to normal after completing troubleshooting.

Supply-Air Sensor Input

To check supply-air sensor input:

1.Make sure EconoMi$er IV preparation procedure has been performed.

2.Set the Enthalpy potentiometer to A. The Free Cool LED turns on. The actuator should drive to between 20 and 80% open.

3.Remove the 5.6 kilo-ohm resistor and jumper T to T1. The actuator should drive fully open.

4.Remove the jumper across T and T1. The actuator should drive fully closed.

5.Return EconoMi$er IV settings and wiring to normal after completing troubleshooting.

EconoMi$er IV Troubleshooting Completion

This procedure is used to return the EconoMi$er IV to operation. No troubleshooting or testing is done by performing the following procedure.

1.Disconnect power at TR and TR1.

2.Set enthalpy potentiometer to previous setting.

3.Set DCV maximum position potentiometer to previous setting.

4.Set minimum position, DCV setpoint, and exhaust potentiometers to previous settings.

5.Remove 620-ohm resistor from terminals SR and +.

6.Remove 1.2 kilo-ohm checkout resistor from terminals SO and +. If used, reconnect sensor from terminals SO and +.

7.Remove jumper from TR to N.

8.Remove jumper from TR to 1.

9.Remove 5.6 kilo-ohm resistor from T and T1. Reconnect wires at T and T1.

10.Remove jumper from P to P1. Reconnect device at P and P1.

11.Apply power (24 vac) to terminals TR and TR1.

WIRING DIAGRAMS

See Fig. 84 and 85 for typical wiring diagrams.

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