Single Enthalpy

To check single enthalpy:

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

2.Set the enthalpy potentiometer to A (fully CCW). The Free Cool LED should be lit.

3.Set the enthalpy potentiometer to D (fully CW). The Free Cool LED should turn off.

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

DCV (Demand Controlled Ventilation) and Power Exhaust

To check DCV and Power Exhaust:

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

2.Ensure terminals AQ and AQ1 are open. The LED for both DCV and Exhaust should be off. The actuator should be fully closed.

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

4.Turn the Exhaust potentiometer CW until the Exhaust LED turns off. The LED should turn off when the po- tentiometer is approximately 90%. The actuator should remain in position.

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 ac- tuator 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 mid- point. 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 previ- ous setting.

4.Set minimum position, DCV setpoint, and exhaust po- tentiometers to previous settings.

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

6.Remove 1.2 kilo-ohm checkout resistor from termin- als SO and +. If used, reconnect sensor from termin- als 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. Recon- nect 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. 83 and Fig. 84 for typical wiring diagrams.

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Carrier 48TCA04---A12 appendix Wiring Diagrams

48TCA04---A12 specifications

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