Carrier 48HC Units without Thru-Base Connections, Field Control Wiring, Thermostat

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48HC

NOTICE/AVIS

Convenience Outlet Utilization

Maximum Intermittent Use 15 - Amps

Maximum Continuous Use 8 - Amps

Observe a 50% limit on the circuit

Loading above 8 - Amps

Utilisation de la prise utilitaire

Usage intermittent maximum 15 - Amps

Usage continu maximum 8 - Amps

Observez une limite de 50% sur le circuit

Chargement au-dessus de 8 - Amps 50HE501288 2.0

C10077

Fig. 29 - Convenience Outlet Utilization Notice

Test the GFCI receptacle by pressing the TEST button on the face of the receptacle to trip and open the receptacle. Check for proper grounding wires and power line phasing if the GFCI receptacle does not trip as required. Press the RESET button to clear the tripped condition.

Using unit-mounted convenience outlets: Units with unit-mounded convenience outlet circuits will often require that two disconnects be opened to de-energize all power to the unit. Treat all units as electrically energized until the convenience outlet power is also checked and de-energization is confirmed. Observe National Electrical Code Article 210, Branch Circuits, for use of convenience outlets.

Factory-Option Thru-Base Connections —

All units are equipped with the ability to bring utilities through the base.

Gas is brought up through an embossed area located in the gas section behind the gas entrance post. Access is gained through the gas access panel. A knock out must be removed to accomplish this.

The electrical entrance is located in the control box area and can be accessed through the control box access panel. An embossed area is provided with three knock outs. High voltage is brought through the multi knock out by removing the appropriate size for the size of the fitting required. A 7/8-in. knock out is provided for low voltage. An additional 7/8-in. knock out is provided for a 115 volt line which is used when the unit is equipped with the non-unit powered convenience outlet option.

All required fittings are field supplied. Install fittings when access to both top and bottom of the base pan is available. See electrical and gas connections for routing and connection information.

Units without Thru-Base Connections —

1.Install liquid tight conduit between disconnect and control box.

2.Pull correctly rated high voltage wires through the conduit.

3.Install power lines to terminal connections as shown in Fig. 25.

Field Control Wiring —

The 48HC unit requires an external temperature control device. This device can be a thermostat (field-supplied) or a PremierLink controller (available as factory-installed option or as field-installed accessory, for use on a Carrier Comfort Network or as a stand alone control) or the RTU Open for Building Management Systems using non-CCN protocols (RTU Open is available as a factory-installed option only).

Thermostat —

Install a Carrier-approved accessory 2-stage thermostat according to installation instructions included with the accessory. Locate the thermostat accessory on a solid wall in the conditioned space to sense average temperature in accordance with the thermostat installation instructions.

If the thermostat contains a logic circuit requiring 24-v power, use a thermostat cable or equivalent single leads of different colors with minimum of seven leads. If the thermostat does not require a 24-v source (no “C” connection required), use a thermostat cable or equivalent with minimum of six leads. Check the thermostat installation instructions for additional features which might require additional conductors in the cable.

For wire runs up to 50 ft. (15 m), use no. 18 AWG (American Wire Gage) insulated wire (35_C minimum). For 50 to 75 ft. (15 to 23 m), use no. 16 AWG insulated wire (35_C minimum). For over 75 ft. (23 m), use no. 14 AWG insulated wire (35_C minimum). All wire sizes larger than no. 18 AWG cannot be directly connected to the thermostat and will require a junction box and splice at the thermostat.

Unit without Thru-Base Connection Kit —

Correctly rated low voltage wire can be routed through the rubber grommet located on the corner post adjacent to the control box access panel. Route wire through the grommet and then route the wire behind the corner post utilizing the factory provided wire ties secured to the control box. This will insure separation of the field low voltage wire and the high voltage circuit. Route the low voltage wire to the central terminal board. See Fig. 30.

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Contents Installation Instructions Safety Considerations Unit Dimensional Drawing 17 Size Unit C10897 Unit Dimensional Drawing 20 and 24 Size Units C10893 Unit Dimensional Drawing 28 Size Unit C10901 Plan for Unit Location Operating WeightsRoof Mount Inspect unit Plan for Sequence of Unit InstallationProvide Unit Support Roof Curb Details 17 Size Unit Roof Curb Details 20 and 24 Size Units Roof Curb Details 28 Size Unit Field Fabricate Ductwork Rig and Place UnitHorizontal Duct Connection Install Outside Air Hood Factory OptionPositioning on Curb To assemble the outside air hood Install Flue Hood and Combustion Air HoodInstall Gas Piping Gas Supply LineTypical 3/4-in NPT Field Supplied Piping Parts Natural Gas Supply Line Pressure RangesFactory-Option Thru-Base Connections Orifice HoleField Power Supply Install External Condensate Trap and LineMake Electrical Connections Units with Factory-Installed Disconnect All UnitsPowered Convenience Outlet Wiring Thermostat Field Control WiringUnits without Thru-Base Connections Unit without Thru-Base Connection KitTransformer Connection for 208-v Power Supply Typical Low-Voltage Control ConnectionsTo connect the Carrier humidistat HL38MG029 Humidi-MiZerRControl ConnectionsHumidi-MiZer Space RH Controller To connect the Thermidistat device 33CS2PPRH-01OAT RRS Srtn PremierLinkt Factory-Option PremierLink ControllerPremierLink Wiring Schematic PremierLink Wiring Schematic with Humidi-MiZerR EconoMi$er2 Supply Air Temperature SAT SensorField Connections PremierLink Sensor UsageSpace Sensor Mode Thermostat ModeConfigure the Unit for Thermostat Mode Space SensorsEconomizer Controls Indoor Air Quality CO2 SensorSpace Relative Humidity Sensor Installation To wire the sensorPower Exhaust output Filter Status SwitchSupply Fan Status Switch Smoke Detector/Fire Shutdown FSDCCN Communication Bus Connecting CCN Bus Color Code RecommendationsRecommended Cables RTU Open Control System RTU Open Multi-Protocol Control BoardRTU Open System Control Wiring Diagram RTU Open System Control Wiring Diagram with Humidi-MiZerR RTU Open Controller Inputs and Outputs Type of I/O Connection PIN Name Numbers Dedicated InputsSpace Temperature SPT Sensors RTU Open T-55 Sensor ConnectionsSpace Relative Humidity Sensor Typical Wiring Relative Humidity Sensors Space or Duct MountedDuct Relative Humidity Sensor Typical Wiring Connecting Discrete InputsCommunication Wiring Protocols GeneralLocal Access RTU Open TroubleshootingLEDs Outdoor Air Enthalpy ControlDifferential Enthalpy Control Return Air Sensor Tube Installation WiringSmoke Detectors Smoke Detector Test Magnet To install the return air sensor sampling tubeUnit Wire/Fuse or Hacr Breaker Sizing Data Additional Application DataUnit NOM IFM FAN Motor Exhaust Unbalanced 3-Phase Supply Voltage EconoMi$er IV Occupancy Switch Adjust Factory-Installed OptionsInstall Accessories Pre-Start and Start-Up48HC Catalog No 48HC---11SI

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.
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