Carrier Air Conditioner specifications Refrigerant Feed Components Each circuit has

Page 58

Refrigerant Feed Components — Each circuit has

all necessary refrigerant controls.

ELECTRONIC EXPANSION VALVE (EXV) — A cut- away view of valve is shown in Fig. 30.

High-pressure liquid refrigerant enters valve through bot- tom. A series of calibrated slots have been machined in side of orifice assembly. As refrigerant passes through orifice, pressure drops and refrigerant changes to a 2-phase condition (liquid and vapor). To control refrigerant flow for different operating conditions, a sleeve moves up and down over orifice and mod- ulates orifice size. A sleeve is moved by a linear stepper motor. Stepper motor moves in increments and is controlled directly by EXV module. As stepper motor rotates, motion is trans- ferred into linear movement by lead screw. Through stepper motor and lead screw, 1500 discrete steps of motion are ob- tained. The large number of steps and long stroke results in very accurate control of refrigerant flow. The minimum posi- tion for operation is 120 steps.

The EXV module controls the valve. The lead compressor in each circuit has a thermistor located in the suction manifold after the compressor motor and a thermistor located in a well where the refrigerant enters the cooler. The thermistors mea- sure the temperature of the superheated gas entering the com- pressor cylinders and the temperature of the refrigerant enter- ing the cooler. The difference between the temperature of the superheated gas and the cooler suction temperature is the su- perheat. The EXV module controls the position of the electron- ic expansion valve stepper motor to maintain superheat set point.

The superheat leaving cooler is approximately 3° to 5° F (2° to 3° C), or less.

Because EXV status is communicated to the Main Base Board (MBB) and is controlled by the EXV modules (see Fig. 31), it is possible to track the valve position. By this means, head pressure is controlled and unit is protected against loss of charge and a faulty valve. During initial start-up, EXV is fully closed. After initialization period, valve position is

of O-ring grease to the housing seal O-ring before installing the motor canister. Reinstall the motor canister assembly. Tighten the motor nut to 15 to 25 ft-lb (20 to 34 N-m).

Check EXV operation using test functions described in the Service Test section on page 29.

MOISTURE-LIQUID INDICATOR — Clear flow of liquid refrigerant indicates sufficient charge in system. Bubbles in the sight glass indicate undercharged system or presence of non- condensables. Moisture in system measured in parts per mil- lion (ppm), changes color of indicator:

Green — moisture is below 45 ppm;

Yellow-green (chartreuse) — 45 to 130 ppm (caution); Yellow (wet) — above 130 ppm.

Change filter drier at first sign of moisture in system.

IMPORTANT: Unit must be in operation at least 12 hours before moisture indicator can give an accurate reading. With unit running, indicating element must be in contact with liquid refrigerant to give true reading.

FILTER DRIER — Whenever moisture-liquid indicator shows presence of moisture, replace filter drier(s). There is one filter drier on each circuit. Refer to Carrier Standard Service Techniques Manual, Chapter 1, Refrigerants, for details on ser- vicing filter driers.

LIQUID LINE SOLENOID VALVE — All TXV units have a liquid line solenoid valve to prevent liquid refrigerant migra- tion to low side of system during the off cycle.

LIQUID LINE SERVICE VALVE — This valve is located immediately ahead of filter drier, and has a 1/4-in. Schrader connection for field charging. In combination with compressor discharge service valve, each circuit can be pumped down into the high side for servicing.

tracked by the EXV module by constantly monitoring amount of valve movement.

The EXV is also used to limit cooler saturated suction tem- perature to 50 F (10 C). This makes it possible for the chiller to start at higher cooler fluid temperatures without overloading the compressor. This is commonly referred to as MOP (maxi- mum operating pressure).

If it appears that EXV is not properly controlling circuit op- eration to maintain correct superheat, there are a number of checks that can be made using test functions and initialization features built into the microprocessor control. See Service Test section on page 29 to test EXVs.

STEPPER

MOTOR (12 VDC)

ORIFICE ASSEMBLY (INSIDE PISTON SLEEVE)

LEAD SCREW

PISTON SLEEVE

NOTE: The EXV orifice is a screw-in type and may be removed for inspection and cleaning. Once the motor canister is removed the orifice can be removed by using the orifice removal tool (part no. TS429). A slot has been cut in the top of the orifice to facilitate removal. Turn orifice counterclockwise to remove. A large screwdriver may also be used.

When cleaning or reinstalling orifice assembly be careful not to damage orifice assembly seals. The bottom seal acts as a liquid shut-off, replacing a liquid line solenoid valve. If the bot- tom seal should become damaged it can be replaced. Remove the orifice. Remove the old seal. Using the orifice as a guide, add a small amount of O-ring grease, to the underside of the or- ifice. Be careful not to plug the vent holes. Carefully set the seal with the O-ring into the orifice. The O-ring grease will hold the seal in place. If the O-ring grease is not used, the seal O-ring will twist and bind when the orifice is screwed into the EXV base. Install the orifice and seal assembly. Remove the orifice to verify that the seal is properly positioned. Clean any O-ring grease from the bottom of the orifice. Reinstall the ori- fice and tighten to 100 in.-lb (11 N-m). Apply a small amount

Fig. 30 — Electronic Expansion Valve (EXV)

 

 

PL-EXVB

 

 

 

1

BRN

A

 

 

1

 

 

 

2

WHT

E

 

 

2

 

 

 

3

 

D

EXV-B

J7

3

RED

 

 

 

 

4

BLK

B

 

 

4

 

 

 

5

GRN

C

 

 

5

 

 

 

 

PL-EXVA

 

 

 

1

 

A

 

 

1

BRN

 

 

 

2

WHT

E

 

 

2

 

 

J6

3

RED

D

EXV-A

3

 

 

4

BLK

B

 

 

4

 

 

 

5

GRN

C

 

 

5

 

 

ELECTRONIC EXPANSION VALVES (EXVs)

Fig. 31 — Printed Circuit Board Connector

58

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Contents Safety Considerations ContentsGeneral ContentsIntroduction Unit Sizes and Modular Combinations 30GUN,R Major System ComponentsUnit Sizes and Modular Combinations 30GTN,R Unit Nominal Section a Section B 30GTN,R Tons Unit 30GTN,RCarrier Comfort Network CCN Interface Control Module CommunicationThermistor Designations Status Switches Output RelayPage 24 V Control Schematic, Unit Sizes 24 V Control Schematic, Unit Sizes 080-110, 230B-315B CCN LEN Data Communication Port Main Base Board Operating Data 040-110 130-210Thermistor T3 and T4 Locations Compressor Thermistor Locations T7 and T8 Belden 8205 Regular Wiring Plenum Wiring Alpha 1895 AmericanManufacturer Columbia D6451 Manhattan M13402 M64430 Quabik 6130Compressor Protection Control System Module Sizes Stepper Motor 12 VDC CEPL130351 30GUN,R Part Load Data Percent Displacement, Standard UnitsDisplacement Compressors Approx110, 290B 255A 60 Hz390B 60 Hz 330A/B360B 50 Hz 390B 50 HzB1† A1,B1 A1†,A2,B1 A1*,B1†,B2 Unloaded compressor Two unloaders, both unloaded 170, 270A 190, 290A, 360A/BA1*,B1*,B2 Required Hardware for Additional Unloaders 150-210Head Pressure Control PumpoutPower FAN Arrangement FAN Relay Normal ControlService Test See Both main power Scrolling Marquee DisplayModes GEN.O TestStrt Run Status Mode and Sub-Mode DirectorySUB-MODE Keypad Range Item Expansion Comment Entry View VersSUB-MODE Keypad Range Item Expansion Comment Entry Test Service Test Mode and Sub-Mode DirectoryOuts Pressure Mode and Sub-Mode Directory Temperature Mode and Sub-Mode DirectorySet Point Mode and Sub-Mode Directory SUB-MODE Keypad Range Item Expansion Comment Entry GEN.I Inputs Mode and Sub-Mode DirectoryReading and Changing Chilled Fluid Set Point CrctConfiguration Mode and Sub-Mode Directory Outputs Mode and Sub-Mode DirectorySUB-MODE Keypad Range Item Expansion Comment Entry GEN.O CCN OPT1OPT2 EMM240 RsetExample of Temperature Reset Return Fluid Configuration SUB-MODE Keypad Display Item Expansion Comment Entry RsetExample of Configuring Dual Chiller Control Slave Chiller Example of Configuring Dual Chiller Control Master ChillerSUB-MODE Keypad Entry Display Item Expansion Comment Rset SUB-MODE Keypad Display Item Expansion Comment Entry OPT2 Example of Compressor Lead/Lag ConfigurationTime Clock Mode and Sub-Mode Directory SUB-MODE Keypad Entry Item Expansion Comment Range TimeSetting an Occupied Time Schedule Operating Mode and Sub-Mode DirectoryMode no Item Expansion Description Operating ModesAlarms Mode and Sub-Mode Directory Example of Reading and Clearing AlarmsConfiguration Configuring Temperature ResetMode Keypad SUB-MODE Entry ExpansionRED LED Entry Expansion Configuration Configuring Demand Limit DLS2Troubleshooting To 20 mA Demand LimitingPage Alarm and Alert Codes T051FSM By Control Method Cause Code Alert GENERATED?EWT LCWT170 T153T155 T173T205 T203T204 T206Oil Charge ServiceElectronic Components Compressor OIL RequiredCooler Thermistor Locations Plugs Components for Part Number PluggingCondenser Coils Cooler Head Bolt Tightening Sequence Typical Tube SheetCondenser Fan Adjustment Hz Low Noise Fan Option Units Dimension FAN TypePrinted Circuit Board Connector Refrigerant Feed Components Each circuit hasThermistors Temperature Sensors Drop B 5K Thermistor Temperature F vs Resistance/VoltageDrop a 5K Thermistor Temperature C vs Resistance/Voltage Temp Voltage Resistance Drop 200,510 30GTN,R Units Pressure Switch Settings Psig kPaSwitch Cutout CUT-IN 30GUN,R UnitsPRE-START-UP System CheckMaximum Ambient Temperature 125 Temperature Limits for Standard UnitsTemperature START-UP and OperationRefrigerant Circuit Field WiringNominal and Minimum Cooler Fluid Flow Rates CWP ALMHgbps Energy Management Module EMM Wiring Compressor Expansion Board CXB Accessory Wiring Description Status Default Units Point Unit Configuration SettingsOPTIONS1 Options Configuration Description Status Default PointAlarmdef Alarm Definition Table OPTIONS2 Options ConfigurationAppendix a CCN Tables Resetcon Temperature Reset and Demand Limit Brodefs Broadcast POC Definition TableCircadio Circuit a Discrete Parameters Aunit General Unit ParametersCircaan Circuit a Analog Parameters Description Status Units Point ForceableCircban Circuit B Analog Parameters Circbdio Circuit B Discrete ParametersOptions Unit Parameters Strthour Description Status Units PointDescription Status Units Point Defaults CurrmodsLine Description Point CSM/FSM Equipment Table Type 621H, BlockDescription Status Point Appendix B Fluid Drop Pressure Curves Cooler Fluid Pressure Drop Curves 30GUN,GUR040-110Cooler Fluid Pressure Drop Curves 30GUN,GUR130-210 Appendix B Fluid Drop Pressure CurvesCooler Pressure Drop KEY Appendix B Fluid Drop Pressure Curves Cooler Fluid Pressure Drop Curves 30GUN,GUR230B-315B Cooler Fluid Pressure Drop Curves 30GTN,GTR040-110 Cooler Fluid Pressure Drop Curves 30GTN,GTR130-210 Appendix B Fluid Drop Pressure Curves Module B 30GTN,GTR230,245 Module B 30GTN,GTR255,290,315 Service Training Call for Free CatalogRemove and use for job file Preliminary Information START-UP Checklist for Comfortlink Chiller SystemsEquipment Chiller Model no Preliminary Equipment Check Check box if complete System Fluid Volume in Loop Type System UnitStart-UpUnit Start-Up Ccnb Description Status Units Value CtrlCcna BaudSlct Heating Cooling Setpoint Select CND.P RMT.A All Units

Air Conditioner specifications

Carrier Air Conditioners have long been synonymous with reliability and innovation in climate control. Founded by Willis Carrier, the inventor of modern air conditioning, the brand has continuously set industry standards through state-of-the-art technologies and features designed to enhance indoor comfort.

One of the standout features of Carrier air conditioners is their energy efficiency. Many models are equipped with advanced inverter technology, allowing the compressor to adjust its speed based on the cooling demand. This results in decreased energy consumption, which not only reduces utility bills but also lessens the environmental impact. Recognizing the importance of sustainable practices, Carrier has integrated eco-friendly refrigerants into their systems, further promoting energy-efficient operations.

Carrier also emphasizes user comfort through its variable speed systems. These systems maintain consistent temperatures while minimizing temperature fluctuations, ensuring an even distribution of cool air throughout the home. Additionally, many Carrier models come with advanced air filtration systems, designed to capture allergens, dust, and other particulates, thereby improving indoor air quality.

The smart technology featured in Carrier air conditioners plays a key role in modern convenience. Many units are compatible with smart home systems, allowing users to control settings remotely via smartphones or voice-activated devices. With features like programmable thermostats, users can easily set cooling schedules to match their lifestyle, ensuring comfort while maximizing energy savings.

Durability and noise reduction are also central to the Carrier brand. Many models are designed with sound-dampening features, making them some of the quietest units on the market. This is particularly advantageous for residential use, where noise can disrupt daily activities and sleep.

In terms of design, Carrier air conditioners come in various styles and capacities to suit a wide range of spaces, from compact apartment units to large central systems for sprawling homes. Their extensive warranty and service offerings further reinforce Carrier’s commitment to customer satisfaction.

In conclusion, Carrier air conditioners represent a perfect blend of cutting-edge technology, energy efficiency, and user comfort. Their emphasis on sustainability and smart features positions them as a leading choice for homeowners seeking reliable and innovative climate control solutions. Whether for cooling a small room or an entire house, Carrier remains a trusted name in air conditioning.