Carrier 50KC04-06 Service And Maintenance Instructions

377. If connected, remove sensor from terminals SO and +.Connect 1.2 kilo-ohm 4074EJM checkout resistor acrossterminals SO and +.8. Put 620-ohm resistor across terminals SR and +.9. Set minimum position, DCV set point, and exhaust poten-tiometers fully CCW (counterclockwise).10. Set DCV maximum position potentiometer fully CW(clockwise).11. Set enthalpy potentiometer to D.12. Apply power (24 vac) to terminals TR and TR1.DIFFERENTIAL ENTHALPYTo check differential enthalpy:1. Make sure EconoMi$er IV preparation procedure has beenperformed.2. Place 620-ohm resistor across SO and +.3. Place 1.2 kilo-ohm resistor across SR and +. The FreeCool LED should be lit.4. Remove 620-ohm resistor across SO and +. The Free CoolLED should turn off.5. Return EconoMi$er IV settings and wiring to normal aftercompleting troubleshooting.SINGLE ENTHALPYTo check single enthalpy:1. Make sure EconoMi$er IV preparation procedure has beenperformed.2. Set the enthalpy potentiometer to A (fully CCW). TheFree Cool LED should be lit.3. Set the enthalpy potentiometer to D (fully CW). The FreeCool LED should turn off.4. Return EconoMi$er IV settings and wiring to normal aftercompleting troubleshooting.DCV (DEMAND CONTROLLED VENTILATION) ANDPOWER EXHAUSTTo check DCV and Power Exhaust:1. Make sure EconoMi$er IV preparation procedure has beenperformed.2. Ensure terminals AQ and AQ1 are open. The LED forboth DCV and Exhaust should be off. The actuator shouldbe fully closed.3. Connect a 9-v battery to AQ (positive node) and AQ1(negative node). The LED for both DCV and Exhaustshould turn on. The actuator should drive to between 90%and 95% open.4. Turn the Exhaust potentiometer CW until the ExhaustLED turns off. The LED should turn off when the potenti-ometer is approximately 90%. The actuator should remainin position.5. Turn the DCV set point potentiometer CW until the DCVLED turns off. The DCV LED should turn off when thepotentiometer is approximately 9-v. The actuator shoulddrive fully closed.6. Turn the DCV and Exhaust potentiometers CCW until theExhaust LED turns on. The exhaust contacts will close 30to 120 seconds after the Exhaust LED turns on.7. Return EconoMi$er IV settings and wiring to normal aftercompleting troubleshooting.DCV MINIMUM AND MAXIMUM POSITIONTo check the DCV minimum and maximum position:1. Make sure EconoMi$er IV preparation procedure has beenperformed.2. Connect a 9-v battery to AQ (positive node) and AQ1(negative node). The DCV LED should turn on. The actua-tor should drive to between 90% and 95% open.3. Turn the DCV Maximum Position potentiometer to mid-point. The actuator should drive to between 20% and 80%open.4. Turn the DCV Maximum Position potentiometer to fullyCCW. The actuator should drive fully closed.5. Turn the Minimum Position potentiometer to midpoint.The actuator should drive to between 20% and 80% open.6. Turn the Minimum Position Potentiometer fully CW. Theactuator should drive fully open.7. Remove the jumper from TR and N. The actuator shoulddrive fully closed.8. Return EconoMi$er IV settings and wiring to normal aftercompleting troubleshooting.SUPPLY-AIR SENSOR INPUTTo check supply-air sensor input:1. Make sure EconoMi$er IV preparation procedure has beenperformed.2. Set the Enthalpy potentiometer to A. The Free Cool LEDturns on. The actuator should drive to between 20% and80% open.3. Remove the 5.6 kilo-ohm resistor and jumper T to T1. Theactuator should drive fully open.4. Remove the jumper across T and T1. The actuator shoulddrive fully closed.5. Return EconoMi$er IV settings and wiring to normal aftercompleting troubleshooting.ECONOMI$ER IV TROUBLESHOOTING COMPLETIONThis procedure is used to return the EconoMi$er IV to opera-tion. No troubleshooting or testing is done by performing thefollowing procedure.1. Disconnect power at TR and TR1.2. Set enthalpy potentiometer to previous setting.3. Set DCV maximum position potentiometer to previoussetting.4. Set minimum position, DCV set point, and exhaust poten-tiometers to previous settings.5. Remove 620-ohm resistor from terminals SR and +.6. Remove 1.2 kilo-ohm checkout resistor from terminals SOand +. 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. Reconnectwires at T and T1.10. Remove jumper from P to P1. Reconnect device at P andP1.11. Apply power (24 vac) to terminals TR and TR1.