Bryant R-22 service manual Cooling and Heating Operation, Compressor Operation on 289B/180B Models

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SYSTEM FUNCTIONS AND SEQUENCE OF OPERATION

The outdoor unit control system has special functions. The following is an overview of the two-stage control functions:

Cooling and Heating Operation

The 286B/187B/289B/180B model utilizes either a standard 2-stage indoor thermostat or Evolution Communication User Interface. With a call for first stage cooling, the outdoor fan, reversing valve, and low stage compressor are energized. If low-stage cannot satisfy cooling demand, high-stage cooling is energized by the second stage of indoor thermostat or User Interface. After second stage is satisfied, the unit returns to low-stage operation until first stage is satisfied or until second stage is required again. When both first stage and second stage cooling are satisfied, the compressor will shut off. The reversing valve will remain energized until the control board power is removed or a call for heating in initiated. With a call for heating, the outdoor fan and compressor are energized. The compressor will operate in high or low stage operation, as needed to meet the heating demand. When the heating demand is satisfied, the compressor and fan will shut off. The reversing valve is de-energized in the heating mode.

NOTE: When two-stage unit is operating at low-stage, system vapor (suction) pressure will be higher than a standard single-stage system or high-stage operation.

NOTE: Outdoor fan motor will continue to operate for one minute after compressor shuts off, when outdoor ambient is greater than or equal to 100°F. This reduces pressure differential for easier starting on next cycle.

NOTE: If unit has not operated within the past 12 hours, or following a unit power-up, upon the next thermostat high- or low-stage demand, unit operates for a minimum of 5 minutes in high-stage.

On models with non-communicating (non-Evolution) systems, with first stage of cooling, Y1 and O are powered on; and with second stage of cooling, Y1, Y2, and O are on. For these systems, with first stage of heating Y1 is on and for second stage of heating, Y1 and Y2 are on. When the reversing valve is energized, O is powered on.

Communication and Status Function Lights For Evolution Control only, Green communications (COMM) Light

A green LED (COMM light) on the outdoor board indicates successful communication with the other system products. The green LED will remain OFF until communication is established. Once a valid command is received, the green LED will turn ON continuously. If no communication is received within 2 minutes, the LED will be turned OFF until the next valid communication.

Amber Status Light

An amber colored STATUS light is used to display the operation mode and fault codes as specified in the troubleshooting section. See Table 21 for codes and definitions.

NOTE: Only one code will be displayed on the outdoor unit control board (the most recent, with the highest priority).

Utility Interface With Evolution Control

The utility curtailment relay should be wired between R and Y2 connections on the control board for Evolution Communicating Systems only (see Fig. 49.) This input allows a power utility device to interrupt compressor operation during peak load periods. When the utility sends a signal to shut the system down, the User Interface will display, “Curtailment Active”.

Compressor Operation on 289B/180B Models:

The basic scroll design has been modified with the addition of an internal unloading mechanism that opens a bypass port in the first compression pocket, effectively reducing the displacement of the scroll. The opening and closing of the bypass port is controlled by an internal electrically operated solenoid.

The modulated scroll uses a single step of unloading to go from full capacity to approximately 67% capacity. A single speed, high efficiency motor continues to run while the scroll modulates between the two capacity steps. Modulation is achieved by venting a portion of the gas in the first suction pocket back to the low side of the compressor, thereby reducing the effective displacement of the compressor. Full capacity is achieved by blocking these vents, thus increasing the displacement to 100%. A DC solenoid in the compressor controlled by a rectified 24 volt AC signal in the external solenoid plug moves the slider ring that covers and uncovers these vents. The vent covers are arranged in such a manner that the compressor operates at approximately 67% capacity when the solenoid is not energized and 100% capacity when the solenoid is energized.

The loading and unloading of the two step scroll is done “on the fly” without shutting off the motor between steps.

NOTE: 67% compressor capacity translates to approximately 80% cooling or heating capacity at the indoor coil. The compressor will always start unloaded and stay unloaded for five seconds even when the thermostat is calling for high stage.

Fan Motor

Fan motor rotates the fan blade that either draws or blows air through outdoor coil to exchange heat between refrigerant and air. Motors are totally enclosed to increase reliability. This also eliminates need for rain shield.

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Turn off all power to unit before servicing or replacing fan motor. Be sure unit main power switch is turned off.

The bearings are permanently lubricated; therefore, no oil ports are provided.

For suspected electrical failures, check for loose or faulty electrical connections, or defective fan-motor capacitor. Fan motor is equipped with thermal overload device in motor windings which may open under adverse operating conditions. Allow time for motor to cool so device can reset. Further checking of motor can be done with an ohmmeter. Set scale on R X 1 position; check for continuity between three leads. Replace motors that show an open circuit in any of the windings. Place 1 lead of ohmmeter on each motor lead. At same time, place other ohmmeter lead on motor case (ground). Replace any motor that shows resistance to ground, signs of arcing, burning, or overheating.

Located above the compressor is a single-speed fan motor and fan. The 180B/289B air conditioner and heat pump models use the ECM variable speed fan motor.

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Contents Application Guideline Table of ContentsSerial Number Nomenclature Table of Contents TWO Stage NON-COMMUNICATINGTWO Stage Communicating AIR Conditioner and Heat Pump Model Number NomenclatureIntroduction Safety ConsiderationsInstallation Guideline Required Field-Installed Accessories for Heat Pumps AccessoriesRequired Field-Installed Accessories for Air Conditioners Accessory Descriptions LOW-AMBIENT Cooling Guideline Base / Mid-Tier / Deluxe 4-sided Baffle AssemblyDeluxe 3-sided Baffle Assembly and Dimensions Basic Cabinet Designs Cabinet AssemblyLong Line Guideline Access Compressor Or Other Internal Cabinet Components Legacy RNC and Legacy Line Control Box Identification Figure Labels LabelingCapacitor Aluminum WireElectrical ContactorCycle Protector Time-Delay RelayCrankcase Heater Personal Injury Hazard Pressure SwitchesDefrost Control Board Defrost ThermostatIf defrost thermostat is stuck open Troubleshooting HK32EA001 If outdoor unit will not runDefrost Speedup If defrost thermostat is stuck closedHeating Five-Minute Compressor DelayQuiet Shift CoolingLow-Voltage Terminals Troubleshooting HK32EA003Fan Motor Compressor PlugRuns, Does Not Pump Compressor FailuresMechanical Failures Locked RotorSplit Post Grommet part number KA75UG100 Noisy CompressorUnit Personal Injury Hazard Single-Phase MotorsElectrical Failures Compressor Oil Refrigeration SystemRefrigerant Oil Charging Synthetic Roof Precautionary ProcedureServicing Systems on Roofs With Synthetic Materials BrazingPersonal Injury and Unit Damage Hazard Service Valves and PumpdownPumpdown Procedure AccuRaterr Components Used in R-22 Heat Pumps Heating Piston AccuRaterr Heat Pumps OnlyReversing Valve Heating Mode, Solenoid De-Energized Reversing ValveSuction Line Filter Drier Install Liquid-line Filter Drier Indoor ACLiquid Line Filter Drier Accumulator AccumulatorUnit Operation Hazard Install TXVThermostatic Expansion Valve TXV TXV OperationPersonal Injury and Environmental Hazard Make Piping ConnectionsReplacing TXV on an Indoor Coil pre-2006 Replacing TXV on Indoor Coil post-2006Fire Hazard Refrigeration System RepairLeak Detection Coil RemovalSystem Clean-Up After Burnout Compressor Removal and ReplacementDeep Vacuum Method Check ChargeEvacuation Low Superheat with High Suction Pressure Troubleshooting with SuperheatBasic Diagnostics Low Superheat with Normal or Low Suction PressurePseudo Evaporator Superheat Instructions High Superheat with Normal or High Suction PressureHunting Superheat Example Puron System Suction Pressure Drop22 System Suction Pressure Drop Psig PuronrRefrigerant Pressure Temperature ChartPsig 22 Refrigerant Pressure Temperature RelationshipLiquid Line Temperature F Liq Press Subcooling F Psig Puron Subcooling ChartSuperheat F Psig Puron Superheat ChartLiquid Line Temperature F PT F Subcooling F Pres Psig 22 Subcooling Chart22 Superheat Chart Model Plug Information TWO-STAGEApplication Guidelines Model PlugAirflow Selection for 315AAV/355AAV Furnaces General InformationLow Ambient Cooling DefrostAll 286A units must be charged in high stage only Liquid-Line Solenoid AccessoryDefrost Hold Forced DefrostCompressor Operation on 286ANA/187ANA Models One Minute Stage Change Time Delay on 286ANA/187ANA ModelsCooling and Heating Operation Utility Interface With Evolution ControlOutdoor Fan Motor Operation ECM Fan Motor TroubleshootingThermistors Time DelaysMuffler, Accumulator, Reversing Valve RVS Control BOX Troubleshooting Contactor Shorted Detection 230V Line Power Disconnect Detection230v Brown-Out Protection Defeated Compressor Voltage SensingThermistor Sensor Comparison Unloader Test ProcedureTemperature Thermistors Failed Thermistor Default OperationStatus Codes TroubleshootingEdge Thermidistat Models T6-PRH-01 or T6-NRH-01 TWO-STAGE 286B/289B/180B/187B General Information All 286B units must be charged in high stage only Heating Check Chart ProcedureCompressor Operation on 289B/180B Models Low Stage High Stage Low & High Model Contactor And Capacitor Incoming PowerTroubleshooting 187B & 286B Start Circuit Control BoxTroubleshooting HK38EA015 circuit board 289B Compressor Thermal Cutout 286B Models Compressor Thermal CutoutOutdoor Coil Thermistor OCT Attachment Status Codes Single Stage Furnace with 2-Stage Air Conditioner Airflow Selection for FV4C Fan Coils non-communicating TWO Stage NON-COMMUNICATING 127A/226AOperating Ambient Airflow Selections ECM FurnacesDefrost Speedup System Function and Sequence of OperationCompressor Operation Check Charge Indoor Thermostat Control Options TWO Stage Communicating 167A/266AAirflow Selections for ECM Furnaces non communicating Defrost Hold Evolution Controlled Low Ambient CoolingMajor Components For Evolution Control only, Green communications Comm Light Communication and Status Function LightsOutdoor Fan Motor Operation 2230V Brown-Out Protection Defeated Thermistor Curve No 230V at Compressor ContactorOutdoor Coil Thermistor OCT Attachment Status Codes 167A / 266A TroubleshootingCare and Maintenance Puronr R-410A Refrigerant Quick Reference Guide Final Check-OutAIR Conditioner Troubleshooting Chart Heat Pump Troubleshooting Heating Cycle Heat Pump Troubleshooting Cooling Cycle TWO-STAGE 286B/288B 180B/187B Index of TablesDescription Table # TWO-STAGE 286A/288A 180A/187ACatalog No. SM01---6
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R-22 specifications

The Bryant R-22 stands out in the landscape of residential heating and cooling systems with its combination of efficiency, durability, and modern technology. Designed primarily for homeowners seeking comfortable climate control solutions, the R-22 model delivers consistent performance throughout varying seasonal extremes.

One of the main features of the Bryant R-22 is its high energy efficiency. Rated with a SEER (Seasonal Energy Efficiency Ratio) that meets or exceeds industry standards, this air conditioning unit is designed to reduce energy consumption while providing optimal cooling. This not only helps in lowering monthly utility bills but also promotes environmentally responsible usage.

Another notable characteristic is the unit's durability. Constructed with a robust cabinet and high-quality components, the R-22 is built to withstand the rigors of daily use, with protective features that enhance its longevity. The cabinet comes with a powder-coated finish that resists corrosion and harsh weather conditions, ensuring that the unit stays functional and aesthetically pleasing for years.

The Bryant R-22 also incorporates advanced technology to improve user experience. One such innovation is the SmartSet technology, which allows homeowners to program their unit to optimize comfort levels according to their specific needs. This programmable capability enhances energy savings and ensures that the home remains at the desired temperature when residents are present.

Moreover, the unit features a Quiet Operating System that significantly reduces noise levels, making it suitable for residential areas where noise might be a concern. The design minimizes vibrations and optimizes airflow, creating a comfortable environment without disruptive sounds.

For added convenience, the Bryant R-22 is compatible with various thermostat options, including Wi-Fi-enabled models. This allows users to control their home's climate from anywhere using a smartphone app, facilitating effortless adjustments and monitoring of energy usage.

Finally, the Bryant R-22 is backed by a solid warranty, providing peace of mind for homeowners. This commitment to quality and customer satisfaction is a testament to Bryant’s dedication to producing reliable and efficient HVAC solutions. Overall, the Bryant R-22 is an exemplary choice for those looking to enhance their home comfort with the latest in HVAC technology.
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