48HC

 

 

 

 

4-20

24V

 

 

 

RED

 

 

PL6-1 (24-V)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Main

GND

 

 

 

BLK

 

 

PL6-4 (COM)

 

 

 

 

+ VDC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CTB ECON

 

 

 

 

Out

LOW

 

 

 

GRA

 

 

7

 

 

 

 

 

 

 

 

(P’LINK: to J4-2) or

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(RTU Open: to J2-6)

 

 

 

 

Outside Air

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Enthalpy Switch

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

+ 24-36

 

 

 

 

Return Air

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VDC In

 

 

 

 

Enthalpy

 

 

 

 

 

 

4-20 Main

 

 

 

 

Sensor

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Out

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C11161

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 72 - Outside and Return Air Enthalpy Sensor

 

 

 

 

 

 

Wiring

 

 

To wire the return air enthalpy sensor, perform the following:

1.Use a 2-conductor, 18 or 20 AWG, twisted pair cable to connect the return air enthalpy sensor to the enthal- py controller.

2.Connect the field-supplied RED wire to (+) spade connector on the return air enthalpy sensor and the

(+)terminal on the enthalpy controller. Connect the BLK wire to (-) spade connector on the return air en- thalpy sensor and the (-) terminal on the enthalpy controller.

Smoke Detectors

Smoke detectors are available as factory-installed options on 48HC models. Smoke detectors may be specified for Supply Air only or for Return Air without or with economizer or in combination of Supply Air and Return Air. Return Air smoke detectors are arranged for vertical return configurations only. The unit is factory-configured for immediate smoke detector shutdown operation; additional wiring or modifications to unit terminal board may be necessary to complete the unit and smoke detector configuration to meet project requirements.

Return Air Sensor Tube Installation –

The return air sampling tube is shipped in the unit￿s supply fan section, attached to the blower housing (see Fig. 73. Its operating location is in the return air section of the unit (see Fig. 74, unit without economizer, or Fig. 75, unit with economizer), inserted into the return air sensor module housing which protrudes through the back of the control box.

Return Air Sampling Tube

(Shipping Location)

C09102

Fig. 73 - Typical Supply Air Smoke Detector Sensor

Location

Return Air Detector

Sampling Tube

C09135

Fig. 74 - Return Air Sampling Tube Location

in Unit without Economizer

Return Air Detector

Sampling Tube

C09136

Fig. 75 - Return Air Sampling Tube Location

in Unit with Economizer

46

Page 46
Image 46
Carrier 48HC installation instructions Smoke Detectors, Wiring, Return Air Sensor Tube Installation

48HC specifications

The Carrier 48HC is a highly efficient rooftop HVAC unit designed for commercial applications that prioritize both performance and energy savings. This unit embodies Carrier's commitment to innovation by integrating advanced technologies and features that address the modern demands of building climate control.

One of the standout features of the Carrier 48HC is its exceptional energy efficiency. Employing the latest in variable-speed compressor technology, the unit adjusts its output based on the specific cooling needs of the space, which not only enhances comfort levels but also significantly reduces energy consumption. This feature is crucial for businesses looking to lower their operational costs while minimizing their environmental impact.

The Carrier 48HC is also equipped with a comprehensive range of control options. Through its intelligent control systems, users can utilize features such as demand ventilation, which optimizes indoor air quality while maintaining energy efficiency. The integration with building management systems (BMS) further enhances operational effectiveness, allowing real-time monitoring and adjustments from a centralized point.

Additionally, the 48HC is designed with durability in mind. Its robust construction resists harsh weather conditions and ensures long-lasting performance. The unit features advanced corrosion-resistant materials and coatings, which prolong its lifespan and reduce maintenance needs. This durability makes the 48HC a reliable choice for varying environments, whether it’s an industrial setting or a more delicate commercial space.

The unit’s compact design also deserves mention, as it facilitates easier installation on rooftops without taking up excessive space. The modular design allows for customization, enabling businesses to tailor their systems to fit specific heating and cooling requirements.

In terms of comfort, the Carrier 48HC employs efficient air distribution technology that ensures even airflow throughout the space. This greatly enhances occupant comfort by eliminating hot or cold spots, promoting a consistent indoor climate.

Finally, the 48HC complies with stringent environmental regulations and standards. With options for environmentally-friendly refrigerants, it supports businesses in their sustainability efforts while operating effectively under current regulations.

In summary, the Carrier 48HC stands out in the crowded HVAC market due to its advanced technology, energy efficiency, durability, and adaptability for commercial applications, making it a top choice for those looking to invest in a reliable and effective climate control solution.