Bryant R-22 Thermostatic Expansion Valve TXV, TXV Operation, Install TXV, Unit Operation Hazard

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Thermostatic Expansion Valve (TXV)

All fan coils and furnace coils will have a factory installed thermostatic expansion valve (TXV). The TXV will be a bi-flow, hard-shutoff with an external equalizer and a balance port pin. A hard shut-off TXV does not have a bleed port. Therefore, minimal equalization takes place after shutdown. TXVs are specifically designed to operate with Puronr or R-22 refrigerant, use only factory authorized TXV’s. Do not interchange Puron and R-22 TXVs.

TXV Operation

The TXV is a metering device that is used in air conditioning and heat pump systems to adjust to changing load conditions by maintaining a preset superheat temperature at the outlet of the evaporator coil. The volume of refrigerant metered through the valve seat is dependent upon the following:

1.Superheat temperature is sensed by cap tube sensing bulb on suction tube at outlet of evaporator coil. This temperature is converted into pressure by refrigerant in the bulb pushing downward on the diaphragm which opens the valve via the pushrods.

2.The suction pressure at the outlet of the evaporator coil is transferred via the external equalizer tube to the underside of the diaphragm. This is needed to account for the indoor coil pressure drop. Residential coils typically have a high pressure drop, which requires this valve feature.

3.The pin is spring loaded, which exerts pressure on the underside of the diaphragm. Therefore, the bulb pressure works against the spring pressure and evaporator suction pressure to open the valve.

If the load increases, the temperature increases at the bulb, which increases the pressure on the top side of the diaphragm. This opens the valve and increases the flow of refrigerant. The increased refrigerant flow causes the leaving evaporator temperature to decrease. This lowers the pressure on the diaphragm and closes the pin. The refrigerant flow is effectively stabilized to the load demand with negligible change in superheat.

Install TXV

The thermostatic expansion valve is specifically designed to operate with a refrigerant type. Do not use an R-22 TXV on a Puron system, and do not use a Puron valve on an R-22 system. Refer to Product Data Sheet for the appropriate TXV kit number.

!CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

Al indoor coil units must be installed with a hard shut off PuronR TXV metering device.

IMPORTANT: The TXV should be mounted as close to the indoor coil as possible and in a vertical, upright position. Avoid mounting the inlet tube vertically down. The valve is more susceptible to malfunction due to debris if inlet tube is facing down. A factory-approved filter drier must be installed in the liquid line at the indoor unit.

Installing TXV in Place of Piston in a Rated Indoor Coil (pre-2006)

1.Pump system down to 2 psig and recover refrigerant.

2.Remove hex nut from piston body. Use backup wrench on fan coils.

3.Remove and discard factory-installed piston. Be sure Teflon seal is in place.

4.Reinstall hex nut. Finger tighten nut plus 1/2 turn.

NOTE: If the piston is not removed from the body, TXV will not function properly.

!CAUTION

EQUIPMENT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

Use a brazing shield and wrap TXV with wet cloth or use heat sink material

5.Install TXV on indoor coil liquid line. Sweat swivel adapter to inlet of indoor coil and attach to TXV outlet. Use backup wrench to avoid damage to tubing or valve. Sweat inlet of TXV, marked “IN” to liquid line. Avoid excessive heat which could damage valve.

6.Install vapor elbow with equalizer adapter to suction tube of line set and suction connection to indoor coil. Adapter has a 1/4-in. male connector for attaching equalizer tube.

7.Connect equalizer tube of TXV to 1/4-in. equalizer fitting on vapor line adapter.

8.Attach TXV bulb to horizontal section of suction line using clamps provided. Insulate bulb with field-supplied insulation tape. See Fig. 25 for correct positioning of sensing bulb.

9.Proceed with remainder of unit installation.

10 O’CLOCK

2 O’CLOCK

SENSING BULB

STRAP

SUCTION TUBE

A08083

Fig. 25 – Position of Sensing Bulb

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Contents Application Guideline Table of ContentsTWO Stage Communicating Table of Contents TWO Stage NON-COMMUNICATINGAIR Conditioner and Heat Pump Model Number Nomenclature Serial 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 LabelingElectrical Aluminum WireContactor CapacitorCycle Protector Time-Delay RelayCrankcase Heater Personal Injury Hazard Pressure SwitchesDefrost Control Board Defrost ThermostatDefrost Speedup Troubleshooting HK32EA001 If outdoor unit will not runIf defrost thermostat is stuck closed If defrost thermostat is stuck openQuiet Shift Five-Minute Compressor DelayCooling HeatingFan Motor Troubleshooting HK32EA003Compressor Plug Low-Voltage TerminalsMechanical Failures Compressor FailuresLocked Rotor Runs, Does Not PumpSplit Post Grommet part number KA75UG100 Noisy CompressorUnit Personal Injury Hazard Single-Phase MotorsElectrical Failures Compressor Oil Refrigeration SystemRefrigerant Servicing Systems on Roofs With Synthetic Materials Synthetic Roof Precautionary ProcedureBrazing Oil ChargingPersonal 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 AccumulatorThermostatic Expansion Valve TXV Install TXVTXV Operation Unit Operation HazardReplacing TXV on an Indoor Coil pre-2006 Make Piping ConnectionsReplacing TXV on Indoor Coil post-2006 Personal Injury and Environmental HazardLeak Detection Refrigeration System RepairCoil Removal Fire HazardSystem Clean-Up After Burnout Compressor Removal and ReplacementDeep Vacuum Method Check ChargeEvacuation Basic Diagnostics Troubleshooting with SuperheatLow Superheat with Normal or Low Suction Pressure Low Superheat with High 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 Application Guidelines TWO-STAGEModel Plug Model Plug InformationLow Ambient Cooling General InformationDefrost Airflow Selection for 315AAV/355AAV FurnacesDefrost Hold Liquid-Line Solenoid AccessoryForced Defrost All 286A units must be charged in high stage onlyCooling and Heating Operation One Minute Stage Change Time Delay on 286ANA/187ANA ModelsUtility Interface With Evolution Control Compressor Operation on 286ANA/187ANA ModelsOutdoor Fan Motor Operation ECM Fan Motor TroubleshootingThermistors Time DelaysMuffler, Accumulator, Reversing Valve RVS Control BOX Troubleshooting 230v Brown-Out Protection Defeated 230V Line Power Disconnect DetectionCompressor Voltage Sensing Contactor Shorted DetectionTemperature Thermistors Unloader Test ProcedureFailed Thermistor Default Operation Thermistor Sensor ComparisonStatus 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 Troubleshooting 187B & 286B Start Circuit Incoming PowerControl Box Contactor And CapacitorTroubleshooting 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 Operating Ambient TWO Stage NON-COMMUNICATING 127A/226AAirflow Selections ECM Furnaces Airflow Selection for FV4C Fan Coils non-communicatingDefrost 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 Description Table # Index of TablesTWO-STAGE 286A/288A 180A/187A TWO-STAGE 286B/288B 180B/187BCatalog 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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