Start-Up

Fig. 22 Ð Outdoor-Air Hood Details

Use the following information and Start-Up Checklist on page CL-1 to check out unit PRIOR to start-up.

Unit Preparation Ð Check that unit has been installed in accordance with these installation instructions and appli- cable codes.

Compressor Mounting Ð Loosen the compressor hold- down bolts until sidewise movement of the washer under each holddown bolt head can be obtained. Do not loosen completely as bolts are self-locking and will maintain adjustment.

Internal Wiring Ð Check all electrical connections in unit control boxes; tighten as required.

Refrigerant Service Ports and Valves Ð Each 48HJ unit has 2 Schrader-type service ports per circuit; one on the suction line and one on the liquid line. Be sure that the caps on the ports are tight. The units also have 2 service valves per circuit; one on the suction line and one on the discharge line. Be sure all valves are open.

Crankcase Heater Ð Crankcase heater is energized as long as there is power to the unit.

IMPORTANT: Unit power must be on for 24 hours prior to start-up. Otherwise, damage to compressor may result.

Evaporator Fan Ð Fan belt and pulleys are factory in- stalled. See Tables 3A, 3B, 4, and 5 for Fan Performance Data. Remove tape from fan pulley and adjust pulleys on 48HJ015 units as required. See Evaporator-Fan Perfor- mance Adjustment section on page 19. Be sure that fans ro- tate in the proper direction. See Table 6 for air quantity lim- its. See Table 7 for static pressure drops for accessories and options. See Fig. 23 and 24 for fan performance using hori- zontal adapter and power exhaust. To alter fan performance, see Performance Adjustment sections on page 19.

Condenser-Fans and Motors Ð Condenser fans and motors are factory set. Refer to Condenser-Fan Adjustment section on page 20 as required. Be sure that fans rotate in the proper direction.

Return-Air Filters Ð Check that correct ®lters are in- stalled in ®lter tracks (see Table 1). Do not operate unit with- out return-air ®lters.

Outdoor-Air Inlet Screens Ð Outdoor-air inlet screens must be in place before operating unit.

Accessory Field-Installed Economizer Adjust-

ment Ð Remove ®lter access panel. Check that outdoor- air damper is closed and return-air damper is open.

Economizer operation and adjustment are described in Base Unit Operation section on page 17; and Economizer Adjustment section on page 20.

NOTES:

1.Dimensions are in millimeters.

2.The 50DP900211 high static regain adapter accessory may be used to provide horizontal supply/return.

NOTE: The 50DP900211 horizontal supply/return adapter accessory improves 48HJ fan performance by increasing external static pres- sure by amount shown above.

Fig. 23 Ð Horizontal Supply/Return Fan Performance

With 50DP900211 High Static Regain Adapter

48HJ015-025 specifications

The Carrier 48HJ015-025 is a distinguished series of rooftop packaged units renowned for their efficient performance and reliability in light commercial applications. Designed for a variety of indoor environments, these units are engineered to provide efficient heating and cooling solutions, making them suitable for retail spaces, offices, and other commercial buildings.

One of the main features of the Carrier 48HJ series is its advanced scroll compressor technology, which enhances the overall efficiency of the systems. This type of compressor is known for its durability and quiet operation, providing consistent temperature control while minimizing energy consumption. The use of a scroll compressor contributes to a higher Seasonal Energy Efficiency Ratio (SEER) and Heating Seasonal Performance Factor (HSPF), making these units a smart choice for energy-conscious businesses.

Additionally, the 48HJ series incorporates a multi-speed indoor blower that allows for precise airflow control. This feature ensures optimal indoor comfort by adjusting the air distribution based on the specific heating or cooling needs of the space. The ability to adapt to varying load conditions enhances efficiency and reduces energy wastage.

Another noteworthy characteristic of the Carrier 48HJ015-025 is its robust construction. Built with galvanized steel, the units are designed to withstand harsh environmental conditions, ensuring longevity and minimal maintenance requirements. The powder-painted finish offers corrosion resistance, contributing to the unit’s durability over time.

The series also integrates advanced controls for ease of operation. The user-friendly thermostat enables precise temperature management and can be programmed according to the specific needs of the facility. Moreover, compatibility with Building Management Systems (BMS) facilitates seamless integration into existing infrastructure, enabling remote monitoring and enhanced operational efficiency.

In terms of environmental considerations, the Carrier 48HJ series utilizes R-410A refrigerant, which is known for its reduced impact on the ozone layer compared to older refrigerants. This commitment to sustainability aligns with modern environmental standards and regulations.

Overall, the Carrier 48HJ015-025 stands out as a versatile and efficient rooftop packaged unit, perfect for varying commercial applications. Its combination of advanced technology, reliability, and user-focused design makes it a prominent choice for businesses seeking optimized climate control solutions while ensuring sustainability and energy efficiency.