Carrier 50RHE006-060 Refrigerant Charging, Air Coil Fan Motor Removal, Troubleshooting

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5.Read liquid line temperature on thermometer; then subtract from bubble point temperature. The difference equals subcooling temperature.

motor on a high platform such as a step ladder. Do not allow motor to hang by its power wires.

6.Compare the subcooling temperature with the normal temperature listed in Table 9. If the measured liquid line temperature does not agree with the required liquid line temperature, ADD refrigerant to raise the temperature or REMOVE refrigerant (using standard practices) to lower the temperature (allow a tolerance of ± 1.7° C).

Refrigerant Charging

To prevent personal injury, wear safety glasses and gloves when handling refrigerant. Do not overcharge system — this can cause compressor flooding.

NOTE: Do not vent or depressurize unit refrigerant to atmo- sphere. Remove and reclaim refrigerant following accepted practices.

Air Coil Fan Motor Removal

Before attempting to remove fan motors or motor mounts, place a piece of plywood over evaporator coils to prevent coil damage.

Disconnect motor power wires from motor terminals before motor is removed from unit.

1. Shut off unit main power supply.

TROUBLESHOOTING

(Fig. 20 and 21, and Table 16)

When troubleshooting problems with a WSHP, consider the following.

Thermistor — A thermistor may be required for single- phase units where starting the unit is a problem due to low voltage. See Fig. 20 for thermistor nominal resistance.

Control Sensors — The control system employs 2 nom- inal 10,000 ohm thermistors (FP1 and FP2) that are used for freeze protection. Be sure FP1 is located in the discharge fluid and FP2 is located in the air discharge. See Fig. 21.

 

90.0

 

80.0

 

70.0

(kOhm)

60.0

50.0

Resistance

40.0

 

30.0

20.0

10.0

0.0

2.Loosen bolts on mounting bracket so that fan belt can be removed.

3.Loosen and remove the 2 motor mounting bracket bolts on left side of bracket.

4.Slide motor/bracket assembly to extreme right and lift out through space between fan scroll and side frame. Rest

0.020.0 40.0 60.0 80.0 100.0 120.0 140.0 Temperature (degF)

Fig. 20 — Thermistor Nominal Resistance

 

AIR

 

AIRFLOW

COIL

AIRFLOW

 

(°F)

 

(°F)

THERMISTOR

 

EXPANSION

COAX

 

 

VALVE

 

 

FP2

FP1

 

 

CONDENSATE

 

 

 

OVERFLOW

LIQUID

 

 

(CO)

 

 

LINE

WATER IN

WATER OUT

 

AIR COIL

 

WATER

 

 

FREEZE

 

 

PROTECTION

COIL

 

 

 

PROTECTION

 

SUCTION

COMPRESSOR

DISCHARGE

LEGEND

COAX — Coaxial Heat Exchanger

Airflow

Refrigerant Liquid Line Flow

Fig. 21 — FP1 and FP2 Thermistor Location

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Contents Safety Considerations ContentsGeneral InstallationUnit 50RHE Physical Data Aquazone 50RHE006-060 UnitsRight Return Left ReturnTypical Installation 50RHE Units Conversion Left Return, Side Discharge to Back Discharge 50RHE Units Dimensions mm030,036 042,048Typical Ground-Water Piping Installation Water Quality Guidelines Electrical WiringCondition Acceptable Level CAP PSCRVS FP1Comp BMC Loss of Charge Pressure Switch Motorized ValveBlower Motor Capacitor Performance Monitor Blower Relay Sensor, Air Coil Freeze ProtectionTypical Aquazone Deluxe D Control Wiring 3-Phase Unit Electrical Data 50RHE VOLTS-PHASE Voltage Compressor FAN Total MIN MAXUnit Circuit RLA LRA FUSE/HACR FLA50RHE 50RHE Blower PerformanceAirflow Unit SpeedPRE-START-UP Low Voltage Wiring See FigField Selectable Inputs Control Jumper Settings SeeSTART-UP Control Accessory Relay ConfigurationsOperating Limits Unit Start-Up Heating Mode Unit Start-Up Cooling ModeWater Temperature Change Through Heat Exchanger Cooling Heating50RHE Coaxial Water Pressure Drop Typical Unit Operating Pressures and TemperaturesAntifreeze Percentages by Volume Approximate Fluid Volume L Per 30 m of PipeOperation Units with Aquazone Complete C ControlControl LED Code Fault Descriptions Control Current LED Status Alarm Relay OperationsSystem Test Alarm Relay ServiceDescription Status LED Test LED ESDGravity Flow Method Refrigerant Charging TroubleshootingAir Coil Fan Motor Removal Fault Heating Cooling Possible Cause Solution TroubleshootingUnit Does Not Operate Page Page Copyright 2004 Carrier Corporation II. START-UP 50RHE R-407C Unit START-UP ChecklistCooling Cycle Analysis Heating Cycle Analysis

50RHE006-060 specifications

The Carrier 50RHE006-060 is a robust commercial rooftop unit designed for efficient heating and cooling in various applications. This model is part of Carrier’s renowned line of HVAC systems, known for their reliability and performance. With a nominal cooling capacity of 5 tons and heating capacity of 6 tons, this unit is suitable for medium-sized commercial spaces such as retail stores, offices, and schools.

One of the standout features of the Carrier 50RHE006-060 is its advanced scroll compressor technology. This type of compressor is recognized for its efficiency and durability, offering quiet operation while minimizing energy consumption. The inclusion of a variable-speed blower motor enhances comfort by providing consistent airflow while also reducing energy costs by adjusting the speed according to the demand.

Another key characteristic is its integrated microprocessor control system, which allows for precise temperature management. This feature not only provides optimal comfort but also ensures energy savings. The system’s controls can be easily integrated with existing building management systems, allowing for seamless operation and monitoring.

The Carrier 50RHE006-060 boasts enhanced insulation properties, which help reduce noise during operation and improve energy efficiency. Its robust design can withstand various weather conditions, making it a reliable choice for rooftop installation. Moreover, it is designed with accessibility in mind, featuring service doors that allow for easy maintenance, reducing downtime and operational costs.

In terms of efficiency, the unit is designed to meet or exceed EPA energy efficiency standards. It utilizes environmentally friendly refrigerants, adhering to regulations aimed at reducing greenhouse gas emissions. Additionally, the design includes a high-efficiency heat exchanger, which maximizes heat transfer and improves overall performance.

The Carrier 50RHE006-060 is also equipped with a dual-stage heat function, allowing it to provide optimal heating for varying weather conditions, ensuring comfort during the colder months. Furthermore, the unit’s design incorporates features such as hot gas bypass for improved dehumidification, making it adaptable to different climates and enhancing indoor air quality.

In summary, the Carrier 50RHE006-060 stands out with its efficient compressor technology, smart control systems, robust construction, and environmentally conscious design. These features make it a top choice for commercial spaces seeking an effective, reliable, and energy-efficient heating and cooling solution.