5.Press Mode to move through the variables.

6.Press Enter to lock in the selection, then press Mode to continue to the next variable.

Dehumidification of Fresh Air with DCV (Demand Controlled Ventilation) Control

If normal rooftop heating and cooling operation is not adequate for the outdoor humidity level, an energy recovery unit and/or a dehumidification option should be considered.

EconoMi$er IV Preparation

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

NOTE: This procedure requires a 9-v battery, 1.2 kilo-ohm resistor, and a 5.6 kilo-ohm resistor which are not supplied with the EconoMi$er IV.

IMPORTANT: Be sure to record the positions of all potentiometers before starting troubleshooting.

1.Disconnect power at TR and TR1. All LEDs should be off. Exhaust fan contacts should be open.

2.Disconnect device at P and P1.

3.Jumper P to P1.

4.Disconnect wires at T and T1. Place 5.6 kilo-ohm resistor across T and T1.

5.Jumper TR to 1.

6.Jumper TR to N.

7.If connected, remove sensor from terminals SO and +. Connect 1.2 kilo-ohm 4074EJM checkout resistor across terminals SO and +.

8.Put 620-ohm resistor across terminals SR and +.

9.Set minimum position, DCV setpoint, and exhaust po- tentiometers 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 Enthalpy

To check differential enthalpy:

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

2.Place 620-ohm resistor across SO and +.

3.Place 1.2 kilo-ohm resistor across SR and +. The Free Cool LED should be lit.

4.Remove 620-ohm resistor across SO and +. The Free Cool LED should turn off.

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

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.

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Carrier 50TCA04-A07 EconoMi$er IV Preparation, Differential Enthalpy, Single Enthalpy, DCV Minimum and Maximum Position

50TCA04-A07 specifications

The Carrier 50TCA04-A07 is a prominent model from Carrier, a leader in the heating, ventilation, and air conditioning (HVAC) industry. Designed for commercial applications, this unit exemplifies advanced technology and reliability, catering to a wide array of cooling needs.

One of the most notable features of the Carrier 50TCA04-A07 is its high efficiency. With a cooling capacity that suits various settings, it is engineered to provide excellent performance with minimal energy consumption. The unit achieves impressive Seasonal Energy Efficiency Ratio (SEER) ratings, which not only reduce operational costs but also lower the environmental impact.

The Carrier 50TCA04-A07 employs state-of-the-art inverter technology. This innovation allows the compressor to operate at varying speeds, adjusting its output according to the cooling demand. Consequently, the system can maintain optimal comfort levels while using less energy. Additionally, the inverter technology contributes to quieter operation, making it a suitable choice for environments where noise is a concern.

Durability is a hallmark of the Carrier 50TCA04-A07. Constructed with robust materials, this model is designed to withstand harsh conditions and ensure long-term reliability. The unit is equipped with corrosion-resistant components, extending its lifespan and maintaining performance quality over time.

Another significant characteristic of the Carrier 50TCA04-A07 is its advanced control system. The integrated control panel provides easy access to performance settings and monitoring capabilities. Users can effortlessly adjust temperatures and modes, ensuring a customizable climate. Furthermore, compatibility with smart building management systems enhances operational efficiency and real-time monitoring.

Regarding safety features, the Carrier 50TCA04-A07 is equipped with multiple sensors and automated responses to prevent overheating and ensure safe operation. These safety mechanisms not only protect the unit but also contribute to the overall safety of the installation environment.

In summary, the Carrier 50TCA04-A07 is a highly efficient, durable, and technologically advanced HVAC solution for commercial spaces. Its innovative features, including inverter technology, robust construction, and smart control systems, set it apart in the market, making it a reliable choice for businesses seeking to optimize their climate control needs while minimizing energy consumption and operational costs.