Carrier 48HC installation instructions Economizer Controls, Indoor Air Quality CO2 Sensor

Page 32

Economizer Controls

Indoor Air Quality (CO2) Sensor —

The indoor air quality sensor accessory monitors space carbon dioxide (CO2) levels. This information is used to monitor IAQ levels. Several types of sensors are available, for wall mounting in the space or in return duct, with and without LCD display, and in combination with space temperature sensors. Sensors use infrared technology to measure the levels of CO2 present in the space air.

The CO2 sensors are all factory set for a range of 0 to 2000 ppm and a linear mA output of 4 to 20. Refer to the instructions supplied with the CO2 sensor for electrical requirements and terminal locations. See Fig. 46 for typical CO2 sensor wiring schematic.

To connect the sensor to the control, identify the positive (4 to 20 mA) and ground (SIG COM) terminals on the sensor. See Fig. 46. Connect the 4-20 mA terminal to terminal TB3-9 and connect the SIG COM terminal to terminal TB3-11. See Fig. 47.

IAQ Sensor

J4

TB3

PL

4-20mA

9

 

J5-5

 

 

TB3

 

SIG COM 11 J5-3

24 VAC

C11156

Fig. 47 - Indoor CO2 Sensor (33ZCSENCO2)

Connections

Refer to Form 33CS-67SI, PremierLink Installation, Start-up, and Configuration Instructions, for detailed configuration information.

48HC

H G 24 VAC OR

+ - 24 VDC

+ 0-10VDC

- SIG COM + 4-20mA

NC }ALARM

COM RELAY

NO CONTACTS

2 1 8 7 6 5 4 3 2 1

J3 J4

C08635

Outdoor Air Quality Sensor (PNO 33ZCSENCO2 plus weatherproof enclosure) —

The outdoor air CO2 sensor is designed to monitor carbon dioxide (CO2) levels in the outside ventilation air and interface with the ventilation damper in an HVAC system. The OAQ sensor is packaged with an outdoor cover. See Fig. 48. The outdoor air CO2 sensor must be located in the economizer outside air hood.

Fig. 46 - Indoor/Outdoor Air Quality (CO2) Sensor

(33ZCSENCO2) - Typical Wiring Diagram

To accurately monitor the quality of the air in the conditioned air space, locate the sensor near a return-air grille (if present) so it senses the concentration of CO2 leaving the space. The sensor should be mounted in a location to avoid direct breath contact.

Do not mount the IAQ sensor in drafty areas such as near supply ducts, open windows, fans, or over heat sources. Allow at least 3 ft (0.9 m) between the sensor and any corner. Avoid mounting the sensor where it is influenced by the supply air; the sensor gives inaccurate readings if the supply air is blown directly onto the sensor or if the supply air does not have a chance to mix with the room air before it is drawn into the return airstream.

Wiring the Indoor Air Quality Sensor: For each sensor, use two 2-conductor 18 AWG (American Wire Gage) twisted-pair cables (unshielded) to connect the separate isolated 24 vac power source to the sensor and to connect the sensor to the control board terminals.

COVER REMOVED

SIDE VIEW

C07135

Fig. 48 - Outdoor Air Quality Sensor Cover

Wiring the Outdoor Air CO2 Sensor: A dedicated power supply is required for this sensor. A two-wire cable is required to wire the dedicated power supply for the sensor. The two wires should be connected to the power supply and terminals 1 and 2.

To connect the sensor to the control, identify the positive (4 to 20 mA) and ground (SIG COM) terminals on the OAQ sensor. See Fig. 46. Connect the 4 to 20 mA terminal to the TB3-13 terminal of the 48HC. Connect the SIG COM terminal to the TB3-11 terminal of the 48HC. See Fig. 49.

32

Page 31 Page 33
Image 32
Page 31 Page 33
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 Roof Mount Operating WeightsPlan for Unit Location Provide Unit Support Plan for Sequence of Unit InstallationInspect unit 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 UnitPositioning on Curb Install Outside Air Hood Factory OptionHorizontal Duct Connection Install Flue Hood and Combustion Air Hood Install Gas PipingTo assemble the outside air hood Gas Supply LineTypical 3/4-in NPT Field Supplied Piping Parts Natural Gas Supply Line Pressure RangesFactory-Option Thru-Base Connections Orifice HoleMake Electrical Connections Install External Condensate Trap and LineField Power Supply Units with Factory-Installed Disconnect All UnitsPowered Convenience Outlet Wiring Field Control Wiring Units without Thru-Base ConnectionsThermostat Unit without Thru-Base Connection KitTransformer Connection for 208-v Power Supply Typical Low-Voltage Control ConnectionsHumidi-MiZerRControl Connections Humidi-MiZer Space RH ControllerTo connect the Carrier humidistat HL38MG029 To connect the Thermidistat device 33CS2PPRH-01OAT RRS Srtn PremierLinkt Factory-Option PremierLink ControllerPremierLink Wiring Schematic PremierLink Wiring Schematic with Humidi-MiZerR Supply Air Temperature SAT Sensor Field ConnectionsEconoMi$er2 PremierLink Sensor UsageSpace Sensor Mode Thermostat ModeConfigure the Unit for Thermostat Mode Space SensorsEconomizer Controls Indoor Air Quality CO2 SensorSpace Relative Humidity Sensor Installation To wire the sensorFilter Status Switch Supply Fan Status SwitchPower Exhaust output Smoke Detector/Fire Shutdown FSDRecommended Cables Connecting CCN Bus Color Code RecommendationsCCN Communication Bus RTU Open Control System RTU Open Multi-Protocol Control BoardRTU Open System Control Wiring Diagram RTU Open System Control Wiring Diagram with Humidi-MiZerR RTU Open Controller Inputs and Outputs Type of I/O Connection PIN Name Numbers Dedicated InputsSpace Temperature SPT Sensors RTU Open T-55 Sensor ConnectionsSpace Relative Humidity Sensor Typical Wiring Relative Humidity Sensors Space or Duct MountedDuct Relative Humidity Sensor Typical Wiring Connecting Discrete InputsCommunication Wiring Protocols GeneralLocal Access RTU Open TroubleshootingDifferential Enthalpy Control Outdoor Air Enthalpy ControlLEDs Smoke Detectors WiringReturn Air Sensor Tube Installation To install the return air sensor sampling tube Unit Wire/Fuse or Hacr Breaker Sizing DataSmoke Detector Test Magnet Additional Application DataUnit NOM IFM FAN Motor Exhaust Unbalanced 3-Phase Supply Voltage Adjust Factory-Installed Options Install AccessoriesEconoMi$er IV Occupancy Switch 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.
Top Page Image Contents