Carrier 48HJ004---007 Safety Relief, Ventilation Continuous Fan, Heating units without economizer

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A maximum of 9 trips can occur, extending the evaporator-fan off delay to 180 seconds.

To restore the original default value, reset the power to the unit.

To Shut Off Unit —Set system selector switch at off position. Resetting heating selector lever below room temperature will temporarily shut unit off until space temperature falls below thermostat setting.

Step 13 —Safety Relief

A soft solder joint at the suction line fitting provides pressure relief under abnormal temperature and pressure conditions.

Step 14 —Ventilation (Continuous Fan)

Set fan and system selector switches at ON and OFF positions, respectively. Evaporator fan operates continuously to provide constant air circulation. When the evaporator-fan selector switch is turned to the OFF position, there is a 30-second delay before the fan turns off.

Step 15 —Operating Sequence

cooling - units without economizer

When thermostat calls for cooling, terminals G and Y1 are energized. The indoor-fan contactor (IFC), reversing valve solenoid (RVS) and compressor contactor are energized and indoor-fan motor, compressor, and outdoor fan starts. The outdoor fan motor runs continuously while unit is cooling.

heating - units without economizer

When the thermostat calls for heating, terminal W1 is energized. To prevent thermostat short-cycling, the unit is locked into the Heating mode for at least 1 minute when W1 is energized. The induced-draft motor is energized and the burner ignition sequence begins. The indoor (evaporator) fan motor (IFM) is energized 45 seconds after a flame is ignited. On units equipped for two stages of heat, when additional heat is needed, W2 is energized and the high-fire solenoid on the main gas valve (MGV) is energized. When the thermostat is satisfied and W1 is deenergized, the IFM stops after a 45-second time-off delay.

Cooling - units with economi$er iv

When free cooling is not available, the compressors will be controlled by the zone thermostat. When free cooling is available, the outdoor-air damper is modulated by the EconoMi$er IV control to provide a 50_ to 55_F supply-air temperature into the zone. As the supply-air temperature fluctuates above 55_ or below 50_F, the dampers will be modulated (open or close) to bring the supply-air temperature back within the set point limits.

Integrated EconoMi$er IV operation on single-stage units requires a 2-stage thermostat (Y1 and Y2).

For EconoMi$er IV operation, there must be a thermostat call for the fan (G). This will move the damper to its minimum position during the occupied mode.

If the increase in cooling capacity causes the supply-air temperature to drop below 45_F, then the outdoor-air damper position will be fully closed. If the supply-air temperature continues to fall, the outdoor-air damper will close. Control returns to normal once the supply-air temperature rises above 48_F.

If optional power exhaust is installed, as the outdoor-air damper opens and closes, the power exhaust fans will be energized and deenergized.

If field-installed accessory CO2 sensors are connected to the EconoMi$er IV control, a demand controlled ventilation strategy will begin to operate. As the CO2 level in the zone increases above the CO2 set point, the minimum position of the damper will be increased proportionally. As the CO2 level decreases because of the increase in fresh air, the outdoor-air damper will be proportionally closed. Damper position will follow the higher demand condition from DCV mode or free cooling mode.

Damper movement from full closed to full open (or vice versa) will take between 1-1/2 and 2-1/2 minutes.

If free cooling can be used as determined from the appropriate changeover command (switch, dry bulb, enthalpy curve, differential dry bulb, or differential enthalpy), a call for cooling (Y1 closes at the thermostat) will cause the control to modulate the dampers open to maintain the supply air temperature set point at 50_ to 55_ F.

As the supply air temperature drops below the set point range of 50_ to 55_ F, the control will modulate the outdoor-air dampers closed to maintain the proper supply-air temperature.

heating - units with economi$er iv

When the room temperature calls for heat, the heating controls are energized as described in the Heating, Units Without Economizer section. When the thermostat is satisfied, the economizer damper moves to the minimum position.

cooling - units with economi$er2, premierlinkt CONTROL AND A THERMOSTAT

When free cooling is not available, the compressors will be controlled by the PremierLink control in response to the Y1 and Y2 inputs from the thermostat.

The PremierLink control will use the following information to determine if free cooling is available:

SIndoor fan has been on for at least 30 seconds.

SThe SPT, SAT, and OAT inputs must have valid readings.

SOAT must be less than 75_F. S OAT must be less than SPT.

SEnthalpy must be LOW (may be jumpered if an enthalpy sensor not available).

SEconomizer position is NOT forced.

Pre-cooling occurs when there is no call from the thermostat except G. Pre-cooling is defined as the economizer modulates to provide 70_F supply air.

When free cooling is available the PremierLink control will control the compressors and economizer to provide a supply-air temperature determined to meet the Y1 and Y2 calls from the thermostat using the following three routines. The three control routines are based on OAT.

The 3 routines are based on OAT where: SASP = Supply Air Set Point

DXCTLO = Direct Expansion Cooling Lockout Set Point PID = Proportional Integral

Routine 1 (OAT < DXCTLO)

SY1 energized – economizer maintains a SASP = (SATLO1 + 3).

SY2 energized – economizer maintains a SASP = (SATLO2 + 3).

Routine 2 (DXCTLO < OAT < 68_F)

SIf only Y1 energized, the economizer maintains a SASP = (SATLO1 + 3).

SIf SAT > SASP + 5 and economizer position > 80%, economizer will go to minimum position for 3 minutes or until SAT > 68_F.

SFirst stage of mechanical cooling will be energized. S Integrator resets.

SEconomizer opens again and controls to current SASP after stage one on for 90 seconds.

SWith Y1 and Y2 energized Economizer maintains an SASP = SATLO2 + 3.

48HE,HJ

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Contents Electrical Shock Hazard Installation InstructionsAlternate Unit Support FIRE, Explosion HazardRoof Curb 48HE,HJ Positioning Install Flue HoodProperty Damage Hazard 48HJ Unit Operating Dimensions Weight48HE 48HJ004-007 Base Unit Dimensions 48HE003-006 Base Unit Dimensions Heat anticipator settings Field power supplyField control wiring Nominal Capacity Physical Data 48HJHJE HJD Physical Data 48HE HEE HED Power Wiring Connections 48HE003---006 Electrical Data 48HEElectrical Data 48HJ 38.2 242 208/230---3---60 187 254 12.4 Convenience outlet AssemblyHUMIDI-MIZERADAPTIVE Dehumidification System Manual outdoor damperTypical Humidi-MiZer t Adaptive Dehumidification System Enthalpy Sensors and Control Install the Supply Air Temperature SAT SensorOutdoor Air Temperature Sensor OAT Install the Indoor Air Quality CO2 SensorPremierLink Controller PremierLinkSensor UsagePremierLinktController Installed EconoMi$er IV Component Locations Return Air Enthalphy SensorECONOMI$ER IV Standard Sensors Outdoor Air Temperature OAT SensorECONOMI$ER IV Control Modes RUN EconoMi$er IV WiringIndoor Air Quality IAQ Sensor Input Exhaust Set Point AdjustmentDifferential Enthalphy Control Damper Movement Minimum Position ControlThermostats Demand Controlled Ventilation DCV Enthalpy Changeover Set PointsBelt drive motors Adjust Evaporator-Fan SpeedDehumidification of Fresh Air with DCV Control Belt Drive Motor Mounting CO2Sensor Standard SettingsEvaporator-Fan Motor Data High-Static Motors 48HJ Fan Rpm at Motor Pulley Setting With High-Static MotorAccessory static pressure Evaporator-Fan Motor Data Standard MotorAirflow 48HJ Outdoor Sound Power Total Unit48HE Outdoor Sound Power Total Unit Unit ARI Octave Bands Rating1300 Rpm Bhp1100 1200Rpm Bhp Watts 1700 Rpm Bhp WattsWatts Rpm Bhp 1200 16001642 2333 1704 Rpm Bhp Watts 15002800 Watts Rpm Bhp 18002600 2700Bhp 600 Bhp Watts Rpm2700 2800 2900 3000 Watts Rpm Bhp 900 Bhp Watts 900Watts Rpm Bhp Watts 1700 1800 1900 20001900 2000 2100 2200 2300 2400 2500 800 350 904 438 999 535 1087 640 1169 753 913 569 1250 1500 1750 2000 2250 2500 2750 3000 Gas Piping Internal WiringRefrigerant Service Ports Unit PreparationHeating CoolingMain Burners Heating units without economizer Safety ReliefVentilation Continuous Fan Operating Sequence Cooling units without economizerRoutine 3 OAT DX Cooling Temperature Control ExampleNormal Design Operation Subcooling ModeUnits with HUMIDI-MIZERADAPTIVE Dehumidification System One-Row Coils CleaningEvaporator Coil Condenser coilLubrication Compressor Condenser-Fan AdjustmentHigh Pressure Switch FiltersHUMIDI-MIZERSYSTEM Charging Cooling Charging Chart Standard 48HJ006 To USE Cooling Charging CHART, Standard Unit Combustion-Air Blower Flue Gas PassagewaysBurner Ignition Limit SwitchLED Error Code Description Removal and Replacement of GAS Train SeeLOW Heat Replacement PartsOFM Economi$er IV troubleshooting completion Unit TroubleshootingEconomi$er IV Troubleshooting Dcv demand controlled ventilation and power exhaustLED OFF LED Error Code Service AnalysisSymptom Cause Remedy Component Damage HazardProblem Cause Remedy Heating Service AnalysisCooling Service Analysis Inputs Outputs EconoMi$er IV Input/Output LogicSTART-UP Checklist

48HJ004---007, 48HE003---006 specifications

Carrier has long been a trusted name in the HVAC industry, and its models 48HJ004---007 and 48HE003---006 continue that legacy, offering efficient, reliable climate control solutions. These models are designed for different applications, ensuring optimal performance in a variety of environments.

The 48HJ series features advanced rooftop units that are ideal for commercial settings. They come equipped with high-efficiency scroll compressors that provide superior cooling and heating capabilities. This series is noted for its compact design, allowing for easy installation on rooftops or other constrained spaces. The units offer variable capacity operation, which enables them to efficiently meet varying heating and cooling demands without unnecessary energy consumption.

One of the standout features of the 48HJ series is its use of advanced microprocessor controls. This technology allows for precise temperature management and system diagnostics, enhancing the ease of operation while ensuring maximum comfort. Additionally, the series supports advanced connectivity options, enabling integration with building management systems. This allows for remote monitoring and control, making it easier for facility managers to keep track of performance and energy usage.

On the other hand, the 48HE series specializes in high-efficiency heating and cooling performance. These units are designed for larger commercial spaces and come with robust features for enhanced durability and efficiency. Like the 48HJ series, the 48HE models utilize scroll compressors and are equipped with a high-efficiency fan setup for improved airflow and reduced noise levels.

The 48HE also includes an innovative heat pump option, which allows the system to reverse the cooling process to provide heating, making it versatile across different seasonal demands. Both series are designed with eco-friendly refrigerants that comply with the latest environmental regulations, ensuring a minimized ecological footprint.

In terms of energy efficiency, both the 48HJ and 48HE series hold impressive SEER and EER ratings, contributing to reduced operational costs over time. The units are also built with durable, corrosion-resistant materials, ensuring longevity and low maintenance needs.

In conclusion, Carrier 48HJ004---007 and 48HE003---006 models are designed with cutting-edge technology, energy efficiency, and flexibility in mind. Their robust features make them ideal choices for commercial applications, providing reliable comfort and operational excellence. Whether for cooling or heating, these systems stand out in performance and sustainability, earning Carrier's reputation as a leader in the HVAC market.
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