Friedrich WS10B10 service manual Testing the Coil, Checking the Reversing Valve

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TESTING THE COIL

WARNING

ELECTRIC SHOCK HAZARD

Unplug and/or disconnect all electrical power to the unit before performing inspections, maintenances or service.

Failure to do so could result in electric shock, serious injury or death.

The solenoid coil is an electromagnetic type coil mounted on the reversing valve and is energized during the operation of the compressor in the heating cycle.

1.Turn off high voltage electrical power to unit.

2.Unplug line voltage lead from reversing valve coil.

3.Check for electrical continuity through the coil. If you do not have continuity replace the coil.

4.Check from each lead of coil to the copper liquid line as it leaves the unit or the ground lug. There should be no continuity between either of the coil leads and ground; if there is, coil is grounded and must be replaced.

5.If coil tests okay, reconnect the electrical leads.

6.Make sure coil has been assembled correctly.

NOTE: Do not start unit with solenoid coil removed from valve, or do not remove coil after unit is in operation. This will cause the coil to burn out.

CHECKING THE REVERSING VALVE

NOTE: You must have normal operating pressures before the reversing valve can shift.

WARNING

HIGH PRESSURE HAZARD

Sealed Refrigeration System contains refrigerant and oil under high pressure.

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

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

Check the operation of the valve by starting the system and switching the operation from “Cooling” to “Heating” and then back to “Cooling”. Do not hammer on valve.

Occasionally, the reversing valve may stick in the heating or cooling position or in the mid-position.

When sluggish or stuck in the mid-position, part of the discharge gas from the compressor is directed back to the suction side, resulting in excessively high suction pressure.

Should the valve fail to shift from coooling to heating, block the air flow through the outdoor coil and allow the discharge

pressure to build in the system. Then switch the system from heating to cooling.

If the valve is stuck in the heating position, block the air flow through the indoor coil and allow discharge pressure to build in the system. Then switch the system from heating to cooling.

Should the valve fail to shift in either position after increasing the discharge pressure, replace the valve.

Dented or damaged valve body or capillary tubes can prevent the main slide in the valve body from shifting.

If you determing this is the problem, replace the reversing valve.

After all of the previous inspections and checks have been made and determined correct, then perform the “Touch Test” on the reversing valve.

Reversing Valve in Heating Mode

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Contents Thru-the-wall Table Of Contents Important Safety Information Your safety and the safety of others are very importantRefrigeration System Hazards Introduction Property Damage HazardsFriedrich wallmaster Model Number Code Sleeve / Chassis Dimensions Performance DataElectrical Data Plug/Outlet/Circuit RatingElectric Shock Hazard Fire HazardTo adjust fan speed Electronic Control OperationTo activate Smart FanWS cool-only models To activate Smart FanWY/WE heat-cool modelsTo set the timer Checking Room TemperatureTo Activate Money Saver WY/WE models To set mode of operation To adjust temperatureTo start unit Error Code Mode Testing the Electronic ControlElectronic Control Panel Automatic component protectionError Codes Listing for WS Models Error Codes Listing for WE/WY ModelsReboot the Control Panel E7 Motor Operation E9 Heat Pump FailureComponents Testing Coil SensorsFAN Motor FAN Motor TestCapacitors Heating ElementDrain PAN Valve Capacitor Check with Capacitor AnalyzerRefrigeration System Sequence of Operation 410A Sealed System Repair Considerations Refrigeration system under high pressure410A Sealed Refrigeration System Repairs Equipment RequiredEquipment Must be Capable Risk of Electric ShockMethod Of Charging / Repairs Burn HazardFreeze Hazard Undercharged Refrigerant Systems Overcharged Refrigerant SystemsRestricted Refrigerant System Hermetic Components Check Metering DeviceCheck Valve Capillary Tube SystemsReversing Valve DESCRIPTION/OPERATION POSITION, 4 Port Reversing ValveTesting the Coil Checking the Reversing ValveProcedure For Changing Reversing Valve Touch Test in Heating/Cooling CycleExplosion Hazard Compressor Checks Single Phase Resistance Test Ground TestCompressor Replacement Recommended procedure for compressor replacementHigh Temperatures Rotary Compressor Special Troubleshooting and Service Routine Maintenance Sleeve / Drain Front CoverClearances Room AIR Conditioner Unit Performance Test Data Sheet Date Model SerialGeneral Troubleshooting Tips General Troubleshooting Tips Cooling only Room AIR Conditioners Troubleshooting Tips Possible Cause Possible Solution Problem Possible Cause Possible Action HEAT/COOL only Room AIR Conditioners Troubleshooting Tips Heat Pump Troubleshooting Troubleshooting Chart Cooling Troubleshooting Chart Heating Heat PumpProblem Electrical Troubleshooting Chart Heat Pump System Cools When Heating is DesiredYES Normal Function of Valve Malfunction of ValvePage Page Page Installation Accessories Mounting Hardware Provided Wall PreparationDescription QTY Installation Requirements MECHANICALCUT/SEVER HazardhazardInstallation Instructions for Baffle Adapter KIT BAK MECHANICALCUT/SEVER HazardWallMaster Thru-the-Wall CUT/SEVERInstallation Instructions Mechanical Hazard MECHANICALCUT/SEVER HazardAssembly & Installation Instructions Installation Instructions Subbase for WS, WE & WY Models Installation Instructions Architectural Grille Model AG MECHANICALCUT/SEVER Hazard WALLMASTER≤ THRU-THE-WALL AIR Conditioners Limited Warranty Technical Support Contact Information Page Page Friedrich AIR Conditioning CO