Carrier 48HJ004---007, 48HE003---006 Heating Service Analysis, Problem Cause Remedy

Page 61

 

Table 42— Heating Service Analysis

 

 

 

PROBLEM

CAUSE

REMEDY

Burners Will Not

Misaligned spark electrodes.

Check flame ignition and sensor electrode positioning. Adjust as needed.

Ignite.

 

 

No gas at main burners.

Check gas line for air purge as necessary. After purging gas line of air, allow gas

 

 

to dissipate for at least 5 minutes before attempting to relight unit.

 

 

Check gas valve.

 

Water in gas line.

Drain water and install drip leg to trap water.

 

No power to furnace.

Check power supply, fuses, wiring, and circuit breaker.

 

No 24 v power supply to control circuit.

Check transformer. Transformers with internal overcurrent protection require a

 

 

cool-down period before resetting. Check 24-v circuit breaker; reset if neces-

 

 

sary.

 

Miswired or loose connections.

Check all wiring and wirenut connections.

 

Burned-out heat anticipator in thermostat.

Replace thermostat.

 

Broken thermostat wires.

Run continuity check. Replace wires, if necessary.

Inadequate Heating.

Dirty air filter.

Clean or replace filter as necessary.

 

Gas input to unit too low.

Check gas pressure at manifold. Clock gas meter for input. If too low, increase

 

 

manifold pressure or replace with correct orifices.

 

Unit undersized for application.

Replace with proper unit or add additional unit.

 

Restricted airflow.

Clean filter, replace filter, or remove any restrictions.

 

Blower speed too low.

Use high speed tap, increase fan speed, or install optional blower, as suitable

 

 

for individual units, Adjust pulley.

 

Limit switch cycles main burners.

Check rotation of blower, thermostat heat anticipator settings, and temperature

 

 

rise of unit. Adjust as needed.

 

Too much outdoor air.

Adjust minimum position.

 

 

Check economizer operation.

Poor Flame

Incomplete combustion (lack of

Check all screws around flue outlets and burner compartment. Tighten as nec-

Characteristics.

combustion air) results in:

essary.

 

Aldehyde odors, CO (carbon monoxide),

Cracked heat exchanger.

 

sooting flame, or floating flame.

 

 

Overfired unit — reduce input, change orifices, or adjust gas line or manifold

 

 

pressure.

 

 

Check vent for restriction. Clean as necessary.

 

 

Check orifice to burner alignment.

Burners Will Not

Unit is locked into Heating mode for a

Wait until mandatory one-minute time period has elapsed or reset power to

Turn Off.

one minute minimum.

unit.

Table 43—Humidi-MiZerAdaptive Dehumidification System Subcooling Mode Service Analysis

PROBLEM

CAUSE

 

REMEDY

Subcooling Mode (Liquid Reheat)

No power to control transformer from

Check power source and evaporator-fan relay. Ensure all

Will Not Energize.

evaporator-fan motor.

wire connections are tight.

 

No power from control transformer to liquid line

1.

Fuse open; check fuse. Ensure continuity of wiring.

 

solenoid valve.

2.

Low-pressure switch open. Cycle unit off and allow

 

 

 

low-pressure switch to reset. Replace switch if it will

 

 

 

not close.

 

 

3. Transformer bad; check transformer.

 

Liquid line solenoid valve will not operate.

1.

Solenoid coil defective; replace.

 

 

2.

Solenoid valve stuck open; replace.

 

Liquid line solenoid valve will not open.

Valve is stuck closed; replace valve.

Low System Capacity.

Low refrigerant charge or frosted evaporator coil.

1.

Check charge amount. Charge per Fig. 64-67.

 

 

2.

Evaporator coil frosted; check and replace low-pres-

 

 

 

sure switch if necessary.

Loss of Compressor Superheat

Thermostatic expansion valve (TXV).

1.

Check TXV bulb mounting, and secure tightly to suc-

Conditions with Subcooling/Reheat

 

2.

tion line.

Dehumidification Coil Energized.

 

Replace TXV if stuck open or closed.

Table 44—Humidi-MiZerAdaptive Dehumidification System Hot Gas Reheat Mode Service Analysis

PROBLEM

CAUSE

 

REMEDY

Reheat Mode Will Not Energize.

No power to control transformer from

Check power source and evaporator-fan relay. Ensure all

 

evaporator-fan motor.

wire connections are tight.

 

No power from control transformer to hot gas

1.

Fuse open; check fuse. Ensure continuity of wiring.

 

line solenoid valve

2.

Low-pressure switch open. Cycle unit off and allow

 

 

 

low-pressure switch to reset. Replace switch if it will

 

 

 

not close.

 

 

3. Transformer bad; check transformer.

 

Hot gas line solenoid valve will not operate.

1.

Solenoid coil defective; replace.

 

 

2.

Solenoid valve stuck closed; replace.

 

Low refrigerant charge or frosted evaporator coil.

1.

Check charge amount. Charge per Fig. 64---67.

 

 

2.

Evaporator coil frosted; check and replace low-pres-

 

 

 

sure switch if necessary.

Loss of Compressor Superheat

Thermostatic expansion valve (TXV).

1.

Check TXV bulb mounting, and secure tightly to suc-

Conditions with Subcooling/Reheat

 

2.

tion line.

Dehumidification Coil Energized.

 

Replace TXV if stuck open or closed.

Excessive Superheat.

Liquid line solenoid valve will not operate.

Valve is stuck, replace valve.

 

Hot gas line solenoid valve will not close.

Valve is stuck; replace valve.

48HE,HJ

61

Image 61
Contents Electrical Shock Hazard Installation InstructionsRoof Curb FIRE, Explosion HazardAlternate Unit Support 48HE,HJ Property Damage Hazard Install Flue HoodPositioning 48HE Unit Operating Dimensions Weight48HJ 48HJ004-007 Base Unit Dimensions 48HE003-006 Base Unit Dimensions Field control wiring Field power supplyHeat anticipator settings 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 HUMIDI-MIZERADAPTIVE Dehumidification System AssemblyManual outdoor damper Convenience outletTypical Humidi-MiZer t Adaptive Dehumidification System Outdoor Air Temperature Sensor OAT Install the Supply Air Temperature SAT SensorInstall the Indoor Air Quality CO2 Sensor Enthalpy Sensors and ControlPremierLink 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 WiringDifferential Enthalphy Control Exhaust Set Point AdjustmentIndoor Air Quality IAQ Sensor Input Thermostats Minimum Position ControlDamper Movement Demand Controlled Ventilation DCV Enthalpy Changeover Set PointsDehumidification of Fresh Air with DCV Control Adjust Evaporator-Fan SpeedBelt drive motors Belt Drive Motor Mounting CO2Sensor Standard SettingsAccessory static pressure 48HJ Fan Rpm at Motor Pulley Setting With High-Static MotorEvaporator-Fan Motor Data Standard Motor Evaporator-Fan Motor Data High-Static Motors48HE Outdoor Sound Power Total Unit 48HJ Outdoor Sound Power Total UnitUnit ARI Octave Bands Rating Airflow1100 Rpm Bhp1200 1300Rpm Bhp Watts Watts Rpm Bhp 1200 Rpm Bhp Watts1600 17001642 2333 1704 Rpm Bhp Watts 15002600 Watts Rpm Bhp 18002700 28002700 2800 2900 3000 Bhp Watts RpmBhp 600 Watts Rpm Bhp Watts 900Watts Rpm Bhp 900 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 Refrigerant Service Ports Internal WiringUnit Preparation Gas PipingMain Burners CoolingHeating Ventilation Continuous Fan Safety ReliefOperating Sequence Cooling units without economizer Heating units without economizerRoutine 3 OAT DX Cooling Temperature Control ExampleUnits with HUMIDI-MIZERADAPTIVE Dehumidification System Subcooling ModeNormal Design Operation Evaporator Coil CleaningCondenser coil One-Row CoilsHigh Pressure Switch Condenser-Fan AdjustmentFilters Lubrication CompressorHUMIDI-MIZERSYSTEM Charging Cooling Charging Chart Standard 48HJ006 To USE Cooling Charging CHART, Standard Unit Combustion-Air Blower Flue Gas PassagewaysLED Error Code Description Limit SwitchRemoval and Replacement of GAS Train See Burner IgnitionLOW Heat Replacement PartsOFM Economi$er IV Troubleshooting Unit TroubleshootingDcv demand controlled ventilation and power exhaust Economi$er IV troubleshooting completionSymptom Cause Remedy LED Error Code Service AnalysisComponent Damage Hazard LED OFFProblem 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.