N1

 

EXH

TR

TR1

N

 

Set

 

 

2V

10V

 

 

 

 

 

P1

EXH

 

24

24 Vac

 

 

Vac

COM

P

 

 

 

Min

HOT

_

T1

 

Pos

+

 

 

T

Open

 

 

 

 

 

 

 

 

DCV

1

2

 

 

Max

 

 

 

 

 

2V

10V

 

 

AQ1

DCV

 

 

5

 

 

 

 

 

 

 

AQ

 

DCV

 

4

SO+

 

Set

3

SO

2V

10V

 

 

 

 

 

 

SR+

Free

 

EF

EF1

 

Cool

 

 

 

SR

B

C

 

 

 

A

D

 

 

C06038

Fig. 46 ---EconoMi$er IV Control

CO2 SENSOR MAX RANGE SETTING

 

6000

 

 

 

 

 

 

(ppm)

5000

 

 

 

 

 

 

 

 

 

 

 

 

 

CONFIGURATION

4000

 

 

 

 

 

800 ppm

 

 

 

 

 

 

3000

 

 

 

 

 

900 ppm

 

 

 

 

 

1000 ppm

 

 

 

 

 

 

2000

 

 

 

 

 

1100 ppm

 

 

 

 

 

 

 

 

 

 

 

 

 

RANGE

1000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

2

3

4

5

6

7

8

 

DAMPER VOLTAGE FOR MAX VENTILATION RATE

C06039

Fig. 47 ---CO2 Sensor Maximum Range Setting

CO2 Sensor Configuration

The CO2 sensor has preset standard voltage settings that can be selected anytime after the sensor is powered up. (See Table 8.)

Use setting 1 or 2 for Carrier equipment. (See Table 8.)

1.Press Clear and Mode buttons. Hold at least 5 seconds until the sensor enters the Edit mode.

2.Press Mode twice. The STDSET Menu will appear.

3.Use the Up/Down button to select the preset number. (See Table 8.)

4.Press Enter to lock in the selection.

5.Press Mode to exit and resume normal operation.

The custom settings of the CO2 sensor can be changed anytime after the sensor is energized. Follow the steps below to change the non-standard settings:

1.Press Clear and Mode buttons. Hold at least 5 seconds until the sensor enters the Edit mode.

2.Press Mode twice. The STDSET Menu will appear.

3.Use the Up/Down button to toggle to the NONSTD menu and press Enter.

4.Use the Up/Down button to toggle through each of the nine variables, starting with Altitude, until the desired setting is reached.

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 Control

Information from ASHRAE indicates that the largest humidity load on any zone is the fresh air introduced. For some applications, a device such as a 62AQ energy recovery unit is added to reduce the moisture content of the fresh air being brought into the building when the enthalpy is high. In most cases, the normal heating and cooling processes are more than adequate to remove the humidity loads for most commercial applications.

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.

Step 9 Adjust Evaporator-Fan Speed

Adjust evaporator-fan speed to meet jobsite conditions.

Tables 9 and 10 show fan rpm at motor pulley settings. Tables 11 and 15 show maximum amp draw of belt-drive motor. Table 14 shows sound data. Refer to Tables 16-35 for performance data. See Table 36 for accessory static pressure drop. See Fig. 48 for the Humidi-MiZersystem static pressure drops.

Belt drive motors

Fan motor pulleys are factory set for speed shown in Table 1 or 2. Check pulley alignment and belt tension prior to start-up.

To change fan speed:

1.Shut off the unit power supply and tag disconnect.

2.Loosen the belt by loosening the fan motor mounting nuts. (See Fig. 49.)

3.Loosen movable pulley flange setscrew. (See Fig. 50.)

4.Screw movable flange toward fixed flange to increase speed and away from fixed flange to decrease speed. Increasing fan speed increases load on motor. Do not exceed maximum speed specified in Table 1 or 2.

5.Set movable flange at nearest keyway of pulley hub and tighten setscrew. (See Table 1 or 2 for speed change for each full turn of pulley flange.)

6.Adjust belt tension and align gan and motor pulleys per guidance below.

To align fan and motor pulleys, loosen fan pulley setscrews and slide fan pulley along fan shaft. Make angular alignment by loosening motor from mounting.

Additional motor and fan alignment, as well as angular alignment can be made by loosening the four motor mounting bolts from the mounting plate.

To adjust belt tension:

1.Loosen the two motor mounting nuts as shown in Fig. 49. Some models may have a third mounting nut located on the opposite side of the fan motor mounting plate.

2.Slide motor mounting plate away from fan scroll for proper belt tension (1/2-in. deflection with 8 to 10 lb of force) and tighten mounting nuts.

3.Adjust lock bolt and nut on mounting plate to secure motor in fixed position.

48HE,HJ

29

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Image 29
Carrier 48HJ004---007 Dehumidification of Fresh Air with DCV Control, Adjust Evaporator-Fan Speed, Belt drive motors

48HJ004---007, 48HE003---006 specifications

Carrier has long been a trusted name in the HVAC industry, and its models 48HJ004---007 and 48HE003---006 continue that legacy, offering efficient, reliable climate control solutions. These models are designed for different applications, ensuring optimal performance in a variety of environments.

The 48HJ series features advanced rooftop units that are ideal for commercial settings. They come equipped with high-efficiency scroll compressors that provide superior cooling and heating capabilities. This series is noted for its compact design, allowing for easy installation on rooftops or other constrained spaces. The units offer variable capacity operation, which enables them to efficiently meet varying heating and cooling demands without unnecessary energy consumption.

One of the standout features of the 48HJ series is its use of advanced microprocessor controls. This technology allows for precise temperature management and system diagnostics, enhancing the ease of operation while ensuring maximum comfort. Additionally, the series supports advanced connectivity options, enabling integration with building management systems. This allows for remote monitoring and control, making it easier for facility managers to keep track of performance and energy usage.

On the other hand, the 48HE series specializes in high-efficiency heating and cooling performance. These units are designed for larger commercial spaces and come with robust features for enhanced durability and efficiency. Like the 48HJ series, the 48HE models utilize scroll compressors and are equipped with a high-efficiency fan setup for improved airflow and reduced noise levels.

The 48HE also includes an innovative heat pump option, which allows the system to reverse the cooling process to provide heating, making it versatile across different seasonal demands. Both series are designed with eco-friendly refrigerants that comply with the latest environmental regulations, ensuring a minimized ecological footprint.

In terms of energy efficiency, both the 48HJ and 48HE series hold impressive SEER and EER ratings, contributing to reduced operational costs over time. The units are also built with durable, corrosion-resistant materials, ensuring longevity and low maintenance needs.

In conclusion, Carrier 48HJ004---007 and 48HE003---006 models are designed with cutting-edge technology, energy efficiency, and flexibility in mind. Their robust features make them ideal choices for commercial applications, providing reliable comfort and operational excellence. Whether for cooling or heating, these systems stand out in performance and sustainability, earning Carrier's reputation as a leader in the HVAC market.