Safety Considerations

48/50PD

Variable Frequency Drive (VFD)	53
Integrated Gas Control (IGC) Board	54
Low Voltage Terminal Strip (TB1)	55
Scrolling Marquee Display	56
Accessory Navigatort Display	56
Carrier Comfort Network (CCN)R Interface	56
Field-Installed Accessories	56
SERVICE	59
Cleaning	60
Lubrication	62
Evaporator Fan Service and Replacement	62
Evaporator Fan Performance Adjustment	62
Evaporator Fan Belt Tension Adjustment	63
Variable Frequency Drive (VFD) Replacement	63
Condenser-Fan Adjustment	63
Verify Sensor Performance	64
Economizer Operation During Power Failure	64
Evacuation	64
Refrigerant Charge	64
Gas Valve Adjustment (48PD Units Only)	65
High Altitude (48PD Units Only)	66
Main Burners (48PD Units Only)	66
Filter Drier	66
Protective Devices	66
Relief Devices	67
Compressor Sound Shield	67
Control Circuit, 24-V	67
Replacement Parts	67
Diagnostic LEDs	67
APPENDIX A - LOCAL DISPLAY AND
CCN TABLES	68
APPENDIX B - STARTUP DATA	81
APPENDIX C - ADDITIONAL STARTUP DATA	91
APPENDIX D - ADDITIONAL STARTUP DATA	100
UNIT START-UP CHECKLIST	105

Installation and servicing of air-conditioning equipment can be hazardous due to system pressure and electrical components. Only trained and qualified service personnel should install, repair, or service air-conditioning equipment. Untrained personnel can perform the basic maintenance functions of replacing filters. Trained service personnel should perform all other operations.

When working on air-conditioning equipment, observe precautions in the literature, tags and labels attached to the unit, and other safety precautions that may apply. Follow all safety codes. Wear safety glasses and work gloves. Use quenching cloth for unbrazing operations. Have fire extinguishers available for all brazing operations.

Follow all safety codes. Wear safety glasses and work gloves. Have fire extinguisher available. Read these instructions thoroughly and follow all warnings or cautions attached to the unit. Consult local building codes and National Electrical Code (NEC) for special requirements.

Recognize safety information. This is the safety-alert symbol . When you see this symbol on the unit and in instructions or manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies a hazard which could result in personal injury or death. CAUTION is used to identify unsafe practices which may result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause personal injury or death.

Before performing service or maintenance operations on unit, turn off main power switch to unit and install lockout tag. Ensure electrical service to rooftop unit agrees with voltage and amperage listed on the unit rating plate.

!CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may cause equipment damage.

This unit uses a microprocessor-based electronic control system. Do not use jumpers or other tools to short out components or to bypass or otherwise depart from recommended procedures. Any short-to-ground of the control board or accompanying wiring may destroy the electronic modules or electrical components.

!WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

Improper installation, adjustment, alteration, service, or maintenance can cause property damage, personal injury, or loss of life. Refer to the User’s Information Manual provided with this unit for more details.

Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.

What to do if you smell gas:

1.DO NOT try to light any appliance.

2.DO NOT touch any electrical switch, or use any

phone in your building.

3.IMMEDIATELY call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions.

4.If you cannot reach your gas supplier, call the fire department.

48/50PD05 specifications

The Carrier 48/50PD05 is a remarkable addition to Carrier's lineup of rooftop units, offering advanced cooling and heating solutions for commercial applications. Designed for medium-sized buildings, this unit is well-suited for both new installations and as a replacement for older systems, thanks to its versatile features and efficient performance.

One of the standout features of the 48/50PD05 is its energy efficiency. It incorporates state-of-the-art technology to achieve high Seasonal Energy Efficiency Ratios (SEER) and EER ratings, reducing operational costs while delivering superior comfort. The unit is also compliant with the latest energy regulations, making it an environmentally friendly choice for building owners concerned about sustainability.

The 48/50PD05 is equipped with a highly efficient scroll compressor, which not only enhances performance but also contributes to quiet operation. This is a significant advantage in commercial spaces where noise levels need to be kept in check for comfort and productivity. Additionally, the unit includes advanced airflow design, ensuring even distribution of conditioned air throughout the space.

Technologically, the Carrier 48/50PD05 features Carrier's Infinity Control system, which allows for precise control of indoor climate. This intelligent control mechanism can be integrated with smart building management systems, enabling users to monitor and manage energy use effectively. Wi-Fi connectivity is also available, providing remote access for real-time adjustments and diagnostics.

Durability is another characteristic of the 48/50PD05. Constructed with high-quality materials, the unit withstands various environmental conditions, ensuring longevity and reliability. Moreover, the modular design facilitates easy maintenance, making service procedures efficient and cost-effective.

In addition to cooling, the Carrier 48/50PD05 offers heating capabilities, often utilizing gas or electric heating options that can be tailored to the specific needs of a building. The unit can also be equipped with integrated economizers, allowing for free cooling during suitable outdoor conditions, further enhancing energy savings.

Overall, the Carrier 48/50PD05 stands out as a high-performance HVAC solution that combines efficiency, technology, and durability. It provides building owners with a versatile tool to ensure comfort while minimizing their environmental footprint. With a strong emphasis on energy savings and advanced control features, this rooftop unit is a smart investment for any commercial property.

SERVICE