Carrier 69NT20-531-300 manual Remove all refrigerant using a refrigerant recovery system

Page 68

a. Remove all refrigerant using a refrigerant recovery system.

b.The recommended method to evacuate and dehydrate the system is to connect evacuation hoses at the com- pressor suction, compressor economizer and liquid line service valve (see Figure 6-5). Be sure the ser- vice hoses are suited for evacuation purposes.

c.The area between the suction modulating valve and evaporator expansion valve may not be open to the access valves. To ensure evacuation of this area, check that the suction modulating valve is more than 10% open at controller function code Cd01. If re- quired, the suction modulating valve may be opened by use of the controller function code Cd41 valve override control. If power is not available to open the valve, the area may be evacuated by connecting an additional hose at the low side access valve (item 11, Figure 2-2).

d.Test the evacuation setup for leaks by backseating the unit service valves and drawing a deep vacuum with the vacuum pump and gauge valves open. Shut off the pump and check to see if the vacuum holds. Repair leaks if necessary.

e.Midseat the refrigerant system service valves.

f.Open the vacuum pump and electronic vacuum gauge valves, if they are not already open. Start the vacuum pump. Evacuate unit until the electronic vacuum gauge indicates 2000 microns. Close the electronic vacuum gauge and vacuum pump valves. Shut off the vacuum pump. Wait a few minutes to be sure the vac- uum holds.

g.Break the vacuum with clean dry refrigerant 134a gas. Raise system pressure to approximately 0.2 kg/ cm@ (2 psig), monitoring it with the compound gauge.

h.Remove refrigerant using a refrigerant recovery sys- tem.

i.Repeat steps f.and g. one time.

j.Remove the copper tubing and change the filter-drier. Evacuate unit to 500 microns. Close the electronic vacuum gauge and vacuum pump valves. Shut off the vacuum pump. Wait five minutes to see if vacuum holds. This procedure checks for residual moisture and/or leaks.

k.With a vacuum still in the unit, the refrigerant charge may be drawn into the system from a refrigerant con- tainer on weight scales. Continue to paragraph 6.7

1

2

3

 

 

4

10

8

5

S D

 

 

 

9

7

6

1.

Receiver or Water

5.

Suction Service Valve

 

Cooled Condenser

6.

Vacuum Pump

2.

Compressor

7.

Electronic Vacuum

3.

Discharge Service

 

Gauge

 

Valve

8.

Manifold Gauge Set

4.

Economizer Service

9.

Refrigerant Cylinder

 

Valve

10.

Reclaimer

Figure 6-6. Compressor Service Connections 6.6.4 Procedure - Partial System

a. If the refrigerant charge has been removed from the compressor for service, evacuate only the compressor by connecting the evacuation set-up at the compres- sor service valves. (See Figure 6-6.) Follow evacua- tion procedures of the preceding paragraph except leave compressor service valves frontseated until evacuation is completed.

b. If refrigerant charge has been removed from the low side only, evacuate the low side by connecting the evacuation set-up at the compressor suction and economizer service valves and the liquid service valve except leave the service valves frontseated until evacuation is completed.

c. Once evacuation has been completed and the pump has been isolated, fully backseat the service valves to isolate the service connections and then continue with checking and, if required, adding refrigerant in accordance with normal procedures

T-309

6-4

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Contents Service Model Safety Summary 309 Safety-2 Safety-3 309 Table of Contents Table of Contents Connect Remote Monitoring Check Controller Function CodesValve Replacement Evaporator Coil Replacement Evaporator Heater ReplacementReplacing The Evaporator Fan Assembly Precheck Procedure Checking The Stepper valveElectrical Wiring Schematic Refrigeration Circuit Schematic Standard Operation Refrigeration Circuit Schematic Economized OperationDataCORDER Configuration Variables List of TablesSection Introduction Unit is fitted with a scroll compressorManual, T-300 Section Description Evaporator Section Compressor Section Condenser Section Module which allow communication with a master Communications interface module For further informationModel RSH105 Weight Dry 46.5 kg 103 lb TemperatureApproved Oil Mobil ST32 Oil Charge 2957 ml 100 ounces Oil level range, with the compressor offElectrical Data Safety and Protective Devices Refrigeration Circuit 2.5.1 Standard Operation Standard Operation with Receiver Refrigeration Circuit Schematic -- Economized Operation Temperature Control System Section MicroprocessorKEY Function Controller Software Modes of Operation Perishable Mode -- Economy Controller Alarms Unit PRE-TRIP Diagnostics Thermistor inputssupply & return DCF02=2DCF02=5 Usda thermistor inputs DCF02=6Standard Configuration Download Report Raw Data Report for ABC1234567DataCORDER may be powered up in any one of four ways Logging Interval dCF03DataView DataCORDER Alarms CnF11 Defrost Off Selection NoOFF Std, FullCnF33 Snap Freeze Option SnAPDisplay Only Functions Defrost temperature sensor reading is displayed Possibly delaying a needed defrost cycleSensor Reading Plicable with frozen set pointsController Function Codes Sheet 3 Controller Alarm Indications Sheet 1 Controller Alarm Indications Sheet 2 Controller Alarm Indications Sheet 3 Error Description Memory failureDraw test is done after 15 seconds P1-1Draw test is done after 10 seconds OndsSupply is compared Test failsP6-2 Crease, the test failsPressure switch is open or the condenser fan switch is open Timer is startedDenser fan is started and a 60 second timer is started Requirements Control temperature must be at least 15.6C 60FBy starting P10-0 over Requirements Control temperature must be at least 7.2C 45FSet point, the test proceeds to test Inapplicable Functions Display Title Data 10 DataCORDER Alarm Indications Operation 69NT Fresh AIR MakeupWill be displayed To start a pre-trip test, do the followingWill be displayed Controller Operation -- Perishable Mode Pull Down Falling RisingController Operation -- Frozen Mode Frozen Mode Defrost Section Troubleshooting Unit will not heat or has insuffi Will not initiate defrost Bent motor shaftSuperheat Unit reads abnormal currents Current sensor wiring Check Section Service Valve Frontseated BackseatedCompressor in a deep vacuum, internal dam- age will result Refrigerant Leak Checking Remove all refrigerant using a refrigerant recovery system Refrigerant Charge Compressor Upper Mounting Compressor OIL Level Condenser FAN and Motor Assembly Removing the Expansion Valve Two expansion valves are used, the evaporatorWrapped with Insulating compound. See Cleaned regularly. The preferred cleaning fluid is fresh If applicable, braze the equalizer connection toEqualizer line Check superheat refer to stepStart unit and check operation 14. Unloader Solenoid ValveEvaporator FAN Motor Capacitors Valve Override Controls Precheck Procedure TP1 Mounting Stud Type Cut wires 5 cm 2 inches from shoulder of defec Cut one wire of existing cable 40 mm 1-1/2 inchShorter than the other wire Cut one replacement sensor wire opposite colorMaintenance of Painted Surfaces 23 Door Hinge Repair Crack, Chip & Hole Repair Kit 24. Insert Location In-lbs #10 Ft-lbs 12.72 17.14 In-lbs Ft-lbs 13.99 18.8614.6 49.4 37.08 12.3 41.6 31.25 32.8 24.64 22.7 17.00 11.9 Section Electrical Wiring Schematic Schematic Diagram Wiring Diagram Sheet 1 Wiring Diagram Sheet 2 Index 309 Index-2

69NT20-531-300 specifications

The Carrier 69NT20-531-300 is a cutting-edge rooftop unit designed to meet the demanding requirements of commercial heating and cooling applications. This model embodies Carrier’s commitment to energy efficiency, reliability, and advanced technological features that enhance indoor comfort while minimizing operational costs.

One of the standout features of the Carrier 69NT20-531-300 is its high energy efficiency. It is equipped with advanced compressor technology that optimizes performance while reducing energy consumption. This ensures that businesses can maintain a comfortable indoor climate without incurring exorbitant utility bills. With a high Seasonal Energy Efficiency Ratio (SEER) and Energy Efficiency Ratio (EER), users can expect not only enhanced comfort but also significant cost savings over time.

The cooling capabilities of the 69NT20-531-300 are complemented by its robust heating options. This unit utilizes a gas heat exchanger, ensuring quick and even heating throughout the space. The combination of cooling and heating capabilities in one compact unit makes it a versatile choice for various applications, including retail spaces, offices, and warehouses.

In addition to its impressive performance specifications, the Carrier 69NT20-531-300 incorporates innovative technologies that further enhance its functionality. The unit comes with advanced controls, allowing for precise temperature regulation and zoning capabilities. This ensures that different areas of a building can maintain their desired temperatures based on usage, improving overall energy efficiency.

Durability is another hallmark of the Carrier 69NT20-531-300. The unit is constructed with high-quality materials and features a weather-proof cabinet that protects it from the elements, ensuring long-term reliability even in harsh conditions. Furthermore, its modular design simplifies maintenance, making it easy for technicians to access critical components.

The 69NT20-531-300 is also designed with low noise operation in mind. It employs sound-dampening technology to ensure that operations are quiet, making it an ideal choice for locations where noise reduction is a priority, such as schools or healthcare facilities.

Overall, the Carrier 69NT20-531-300 stands out as a premier choice for businesses looking for an efficient, reliable, and feature-rich rooftop HVAC unit. Its blend of energy efficiency, advanced technology, and durability positions it as a leader in commercial heating and cooling solutions, making it a valuable investment for any commercial property.
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