Friedrich 9, 000 BTU'S service manual Reversing Valve DESCRIPTION/OPERATION, Electric Shock Hazard

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REVERSING VALVE DESCRIPTION/OPERATION

WARNING

ELECTRIC SHOCK HAZARD

Disconnect power to the unit before servicing. Failure to follow this warning could result in serious injury or death.

The Reversing Valve controls the direction of refrigerant flow to the indoor and outdoor coils. It consists of a pressure- operated, main valve and a pilot valve actuated by a solenoid plunger. The solenoid is energized during the heating cycle only. The reversing valves used in the VPAK system is a 2-position, 4-way valve.

The single tube on one side of the main valve body is the high-pressure inlet to the valve from the compressor. The center tube on the opposite side is connected to the low pressure (suction) side of the system. The other two are connected to the indoor and outdoor coils. Small capillary tubes connect each end of the main valve cylinder to the

“A” and “B” ports of the pilot valve.Athird capillary is a common return line from these ports to the suction tube on the main valve body. Four-way reversing valves also have a capillary tube from the compressor discharge tube to the pilot valve.

The piston assembly in the main valve can only be shifted by the pressure differential between the high and low sides of the system. The pilot section of the valve opens and closes ports for the small capillary tubes to the main valve to cause it to shift.

NOTE: System operating pressures must be near normal before valve can shift.

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Contents Single Package Vertical Air Conditioning System Technical Support Contact Information Table of Contents Your safety and the safety of others are very important Important Safety InformationRefrigeration System Hazards Property Damage Hazards IntroductionSerial Number Identification Guide Electric Heat Data Chassis SpecificationsVEA Extended Cooling Performance Extended Cooling PerformanceVEA/VHA09-24 VEA Extended Cooling Performance Electric Shock Hazard Electrical RequirementsRT5 Two speed fan RT4 One speed fan Remote Thermostat and Low Voltage Control ConnectionsThermostat Connections Quiet Start/Stop Electronic Control Board FeaturesElectronic Control Configuration Electronic control error codes diagnostics and test mode DiagnosticsTest Mode Power On and Off Features on the Electronic Control Cool mode control features for cool with electric heat units Compressor operation depends on t-stat settings VERT-I-PAK Single Packaged Vertical AIR Conditioners Component description / A-Series specificationsExternal Static Pressure Indoor Airflow Data Capacitors Components TestingCapacitor Check with Capacitor Analyzer Capacitor ConnectionsComponents Testing Heater Elements and Limit SWITCHES’ SpecificationsDrain PAN Valve Refrigeration Sequence of Operation Refrigeration AssemblyCUT/SEVER Hazard ServiceEquipment Required Sealed Refrigeration System RepairsEquipment Must be Capable Risk of Electric ShockMethod Of Charging / Repairs Burn HazardFreeze Hazard Overcharged Refrigerant Systems Undercharged Refrigerant SystemsRestricted Refrigerant System Metering Device Hermetic Components CheckCheck Valve Capillary Tube SystemsReversing Valve DESCRIPTION/OPERATION Checking the Reversing Valve Testing the CoilTouch Test in Heating/Cooling Cycle Procedure For Changing Reversing ValveFire Hazard Explosion HazardCompressor Checks Single Phase Resistance Test Ground TestChecking Compressor Efficiency Compressor Replacement Recommended procedure for compressor replacementHigh Temperatures Rotary Compressor Special Troubleshooting and Service Coils and Base PAN Excessive Weight Hazard Routine MaintenanceBlower Wheel / Housing / Condenser FAN / Shroud AIR FilterSleeve / Drain Routine MaintenanceFront Cover Condensate Disposal System9K BTU, 12K BTU, & 18K BTU Electrical Troubleshooting Chart CoolingCircuit Breakers are Electrical Troubleshooting Chart Cooling 24K BTUHeat Pump Mode Electrical Troubleshooting Chart Heat PumpTroubleshooting Chart Heating Troubleshooting Chart CoolingElectric Heat VEA 09/12/18 with 2.5 KW, 3.4 KW or 5KWVHA 09/12/18 with 2.5 KW, 3.4 KW or 5KW Cool with Electric Heat Heat Pump with Electric Heat Cool with Electric Heat Heat Pump with Electric Heat Outdoor Coil Return Air Indoor Coil Accessories Wall PlenumDrain PAN Friedrich Air Conditioning Company Technical Support Contact Information Friedrich AIR Conditioning CO