*Shutoff valve not used except where required by code.

Properly cap any gas connection not being used.

Fig. 8 Ð Suggested Gas Piping (48MA)

Unit has factory-installed gas shutoff valves. Install gas shutoff valve external to unit if required by code (Fig. 8). After piping is complete, pressurize gas line and check for leaks with soap and water solution.

Do not use an open ¯ame when checking for gas leaks.

Optional Glycol Connections (50ME) Ð Each zone module has its own glycol heating coil and 115-v solenoid valve. Heating coils are connected in parallel to common sup- ply and return manifolds. Supply manifolds are equipped with bleed cocks. Supply and return connections are shown in Fig. 2 and 5. Unit does not have internal pressure relief for part-load operation. Maximum allowable system working pres- sure is 30 psig. Unit ratings are based on 20% glycol solu- tions. Install solution supply apparatus in accordance with application requirements, and mix glycol solution percent- age in accordance with glycol manufacturer's recommenda- tions. Freeze-up protection is not factory installed.

Field Power Supply Wiring Ð When installed, unit must be electrically grounded in accordance with local codes or, in the absence of local codes, with the National Electrical Code (NEC).

Unit has a circuit breaker for each compressor, each fan motor, and for each 50ME electric resistance heater assem- bly (if unit is so equipped). If required by local code, pro- vide an additional disconnect switch in accordance with code being followed.

All units have a main power supply terminal board in the power and condensing control box. The electric resistance heater power supply terminal board(s) (if unit is so equipped) on 50ME units is located in the heater control box at front of unit. See Fig. 2, 5, and 9.

All terminal boards are suitable for use with copper or aluminum wire.

Connect electrical conduit (a threaded pipe nipple) shipped with unit to threaded ®tting in roof curb and bottom of main power and condensing section control box. Route main power wires through conduit to terminal board in box as shown on unit label wiring diagram and in Fig. 9.

When installing 48MA,50ME040 units with optional 20-hp motor, the electrical conduit interconnecting the curb and con- trol box power wire openings will not accommodate alumi- num wire of the size that may be required. If aluminum wire cannot be accommodated, an external transition box and short lengths of no. 300 kcmil, 75 C copper wire from the tran- sition box to the unit main power connection are recommended.

Voltage to compressor terminals during compressor op- eration must be within voltage range indicated on unit name- plate. Phases must be balanced within 2%.

 

LEGEND

EQUIP

Ð Equipment

GND

Ð Ground

TB

Ð Terminal Board

*208/230 v units only.

Fig. 9 Ð Field Power Supply Details

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Carrier 48MA/50ME016-040 specifications Suggested Gas Piping 48MA
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48MA/50ME016-040 specifications

The Carrier 48MA/50ME016-040 series represents a significant advancement in the field of commercial HVAC systems, designed to provide reliable, efficient, and effective climate control solutions for various applications. These units are widely recognized for their durability and performance, making them a top choice for building owners and managers seeking optimal comfort and energy efficiency.

One of the main features of the Carrier 48MA/50ME series is its advanced scroll compressor technology. The scroll compressors are known for their reliability and efficiency, which leads to reduced energy consumption and lower operating costs. This high-efficiency design not only contributes to significant energy savings but also minimizes noise levels, enhancing the overall comfort of the environment.

The units are equipped with a unique microprocessor-based control system that offers precise temperature control and flexibility. This technology allows for easy integration with building management systems, enabling users to monitor and control their HVAC systems remotely, thereby optimizing performance and energy use. The programmable thermostats help to tailor the operation of the units to meet the specific needs of the users, ensuring maximum comfort at all times.

In addition to its robust performance features, the Carrier 48MA/50ME series also boasts a comprehensive line of options for customization. These options include various cooling capacities ranging from 16 to 40 tons, allowing the equipment to cater to different building sizes and requirements. The series is also designed with a compact footprint, making it suitable for rooftop installations where space is at a premium.

Another important characteristic of the series is its environmentally friendly refrigerant options. Carrier prioritizes the use of refrigerants with low global warming potential, contributing to a more sustainable approach to HVAC solutions. This commitment to environmental responsibility not only complies with regulations but also meets the increasing demand for greener technologies.

Furthermore, the robust construction of the Carrier 48MA/50ME series ensures long-lasting performance in even the harshest conditions. The units are designed to withstand various environmental factors, making them ideal for both commercial and industrial applications. Overall, the Carrier 48MA/50ME016-040 series stands out as a reliable choice for efficient and effective heating and cooling solutions, equipped with innovative technologies that prioritize performance, sustainability, and user comfort.
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