Friedrich 9, 000 BTU'S service manual Restricted Refrigerant System

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Restricted Refrigerant System

Troubleshooting a restricted refrigerant system can be difficult. The following procedures are the more common problems and solutions to these problems. There are two types of refrigerant restrictions: Partial restrictions and complete restrictions.

A partial restriction allows some of the refrigerant to circulate through the system.

With a complete restriction there is no circulation of refrigerant in the system.

Restricted refrigerant systems display the same symptoms as a “low-charge condition.”

When the unit is shut off, the gauges may equalize very slowly.

Gauges connected to a completely restricted system will run in a deep vacuum. When the unit is shut off, the gauges

will not equalize at all.

A quick check for either condition begins at the evaporator. With a partial restriction, there may be gurgling sounds

at the metering device entrance to the evaporator. The evaporator in a partial restriction could be partially frosted or have an ice ball close to the entrance of the metering device. Frost may continue on the suction line back to the compressor.

Often a partial restriction of any type can be found by feel, as there is a temperature difference from one side of the restriction to the other.

With a complete restriction, there will be no sound at the metering device entrance. An amperage check of the compressor with a partial restriction may show normal current when compared to the unit specifi cation. With a complete restriction the current drawn may be considerably less than normal, as the compressor is running in a deep vacuum (no load.) Much of the area of the condenser will be relatively cool since most or all of the liquid refrigerant will be stored there.

The following conditions are based primarily on a system in the cooling mode.

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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 Diagnostics Electronic control error codes diagnostics and test modeTest 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 Capacitor Connections Components TestingCapacitors Capacitor Check with Capacitor AnalyzerHeater Elements and Limit SWITCHES’ Specifications Components TestingDrain PAN Valve Refrigeration Sequence of Operation Refrigeration AssemblyCUT/SEVER Hazard ServiceRisk of Electric Shock Sealed Refrigeration System RepairsEquipment Required Equipment Must be CapableBurn Hazard Method Of Charging / RepairsFreeze Hazard Overcharged Refrigerant Systems Undercharged Refrigerant SystemsRestricted Refrigerant System Capillary Tube Systems Hermetic Components CheckMetering Device Check ValveReversing Valve DESCRIPTION/OPERATION Checking the Reversing Valve Testing the CoilExplosion Hazard Procedure For Changing Reversing ValveTouch Test in Heating/Cooling Cycle Fire HazardCompressor Checks Ground Test Single Phase Resistance TestChecking Compressor Efficiency Recommended procedure for compressor replacement Compressor ReplacementHigh Temperatures Rotary Compressor Special Troubleshooting and Service AIR Filter Routine MaintenanceCoils and Base PAN Excessive Weight Hazard Blower Wheel / Housing / Condenser FAN / ShroudCondensate Disposal System Routine MaintenanceSleeve / Drain Front Cover9K 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 Wall Plenum AccessoriesDrain PAN Friedrich Air Conditioning Company Technical Support Contact Information Friedrich AIR Conditioning CO