Friedrich 000 BTU'S, 9 service manual Hermetic Components Check, Metering Device, Check Valve

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HERMETIC COMPONENTS CHECK

WARNING

BURN HAZARD

Proper safety procedures must be followed, and proper protective clothing must be worn when working with a torch.

Failure to follow these procedures could result in moderate or serious injury.

WARNING

CUT/SEVER HAZARD

Be careful with the sharp edges and corners. Wear protective clothing and gloves, etc.

Failure to do so could result in serious injury.

METERING DEVICE

Capillary Tube Systems

All units are equipped with capillary tube metering devices.

Checking for restricted capillary tubes.

1.Connect pressure gauges to unit.

2.Start the unit in the cooling mode. If after a few minutes of operation the pressures are normal, the check valve and the cooling capillary are not restricted.

3.Switch the unit to the heating mode and observe the gauge readings after a few minutes running time. If the system pressure is lower than normal, the heating capillary is restricted.

4.If the operating pressures are lower than normal in both the heating and cooling mode, the cooling capillary is restricted.

CHECK VALVE

A unique two-way check valve is used on the reverse cycle heat pumps. It is pressure operated and used to direct the flow of refrigerant through a single filter drier and to the proper capillary tube during either the heating or cooling cycle.

One-way Check Valve

(Heat Pump Models)

NOTE: The slide (check) inside the valve is made of teflon. Should it become necessary to replace the check valve, place a wet cloth around the valve to prevent overheating during the brazing operation.

CHECK VALVE OPERATION

In the cooling mode of operation, high pressure liquid enters the check valve forcing the slide to close the opposite port (liquid line) to the indoor coil. Refer to refrigerant flow chart. This directs the refrigerant through the filter drier and cooling capillary tube to the indoor coil.

In the heating mode of operation, high pressure refrigerant enters the check valve from the opposite direction, closing the port (liquid line) to the outdoor coil. The flow path of the refrigerant is then through the filter drier and heating capillary to the outdoor coil.

Failure of the slide in the check valve to seat properly in either mode of operation will cause flooding of the cooling coil. This is due to the refrigerant bypassing the heating or cooling capillary tube and entering the liquid line.

COOLING MODE

In the cooling mode of operation, liquid refrigerant from condenser (liquid line) enters the cooling check valve forcing the heating check valve shut. The liquid refrigerant is directed into the liquid dryer after which the refrigerant is metered through cooling capillary tubes to evaporator. (Note: liquid refrigerant will also be directed through the heating capillary tubes in a continuous loop during the cooling mode).

HEATING MODE

In the heating mode of operation, liquid refrigerant from the indoor coil enters the heating check valve forcing the cooling check valve shut. The liquid refrigerant is directed into the liquid dryer after which the refrigerant is metered through the heating capillary tubes to outdoor coils. (Note: liquid refrigerant will also be directed through the cooling capillary tubes in a continuous loop during the heating mode).

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Contents Single Package Vertical Air Conditioning System Technical Support Contact Information Table of Contents Important Safety Information Your safety and the safety of others are very importantRefrigeration System Hazards Introduction Property Damage HazardsSerial Number Identification Guide Chassis Specifications Electric Heat DataExtended Cooling Performance VEA Extended Cooling PerformanceVEA/VHA09-24 VEA Extended Cooling Performance Electrical Requirements Electric Shock HazardRemote Thermostat and Low Voltage Control Connections RT5 Two speed fan RT4 One speed fanThermostat Connections Electronic Control Board Features Quiet Start/StopElectronic Control Configuration Test Mode Electronic control error codes diagnostics and test modeDiagnostics 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 Component description / A-Series specifications VERT-I-PAK Single Packaged Vertical AIR ConditionersExternal Static Pressure Indoor Airflow Data Components Testing CapacitorsCapacitor Check with Capacitor Analyzer Capacitor ConnectionsDrain PAN Valve Components TestingHeater Elements and Limit SWITCHES’ Specifications Refrigeration Assembly Refrigeration Sequence of OperationService CUT/SEVER HazardSealed Refrigeration System Repairs Equipment RequiredEquipment Must be Capable Risk of Electric ShockFreeze Hazard Method Of Charging / RepairsBurn Hazard Undercharged Refrigerant Systems Overcharged Refrigerant SystemsRestricted Refrigerant System Hermetic Components Check Metering DeviceCheck Valve Capillary Tube SystemsReversing Valve DESCRIPTION/OPERATION Testing the Coil Checking the Reversing ValveProcedure For Changing Reversing Valve Touch Test in Heating/Cooling CycleFire Hazard Explosion HazardCompressor Checks Checking Compressor Efficiency Single Phase Resistance TestGround Test High Temperatures Compressor ReplacementRecommended procedure for compressor replacement Rotary Compressor Special Troubleshooting and Service Routine Maintenance Coils and Base PAN Excessive Weight HazardBlower Wheel / Housing / Condenser FAN / Shroud AIR FilterRoutine Maintenance Sleeve / DrainFront Cover Condensate Disposal SystemElectrical Troubleshooting Chart Cooling 9K BTU, 12K BTU, & 18K BTUElectrical Troubleshooting Chart Cooling 24K BTU Circuit Breakers areElectrical Troubleshooting Chart Heat Pump Heat Pump ModeTroubleshooting Chart Cooling Troubleshooting Chart HeatingVEA 09/12/18 with 2.5 KW, 3.4 KW or 5KW Electric HeatVHA 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 Drain PAN AccessoriesWall Plenum Friedrich Air Conditioning Company Technical Support Contact Information Friedrich AIR Conditioning CO