CHAPTER 25 Installation and Troubleshooting of Domestic Refrigerators and Freezers

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Objectives Check domestic compression refrigerators for proper installation. Use the proper procedure for starting a domestic refrigerator-freezer. Interpret common symptoms of system malfunction. Use proper procedures to test a domestic- refrigerator-freezer’s auxiliary circuits. DiversiTech Corporation

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Objectives Explain the use of piercing valves, pinching tools, and valve adapters. Interpret temperature and pressure conditions inside a refrigeration system to determine points of failure. Summarize common symptoms of internal component failure and their possible causes. Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Proper Installation Move using dolly Locate away from heat and sunlight Easily damaged areas –Bottom (condensing unit) –Back (condenser) –Door (forced out of line or buckled) Adjust shipping bolts Level the unit Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Installing an Ice Maker Run 1/4″ tubing to nearest cold water line –Use enough tubing for several large loops Two water access options –Saddle valve or T-fitting with a shutoff valve Mount saddle valve on water line Connect tubing to valve and refrigerator water line fitting Turn saddle valve to pierce water pipe Check for leaks

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Water Line Access Installation Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Code Alert Consult local plumbing codes before installing an ice maker. –Codes in some areas require the use of a permanent shutoff valve instead of saddle valve. –Codes may also place restrictions on use of compression fittings.

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Checking Electrical Supply Check electrical ratings on appliance against electrical supply at wall outlet Refrigerator-freezer outlet should be on its own separate, isolated circuit Do not use an extension cord Check voltage at outlet with voltmeter or multimeter

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Safety Always check for proper electrical supply and grounding in the electrical outlet box Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Checking for Proper Ventilation Check for adequate space for air movement through and around condenser Limited or confined space –Install only units with forced-draft condensers Units with natural-convection condensers –Allow space at bottom, back, and top of unit Units with hot-wall condensers –Allow at least 2″ (51 mm) between cabinet and surrounding surfaces

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Starting a Refrigerator Test wall outlet with voltmeter Turn temperature control to Off Connect electrical cord to outlet Adjust temperature control to mid-range Make sure refrigerator runs Place in final position After a few hours, check and adjust controls

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Diagnosing a No-Start Condition Check electrical supply circuit –Proper voltage must be accessible Make sure interior lights function –If not, look for problems in electrical supply unit –If lights function, problem is in motor or motor control circuits Visually inspect the electrical circuits –Loose connections, broken wires, etc. Look for mechanical trouble

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Diagnosing Poor Performance Visually inspect the system –Use inspection mirror Use troubleshooting chart to identify causes and remedies Restart system to see if problem was corrected –If not, continue diagnosing system Ritchie Engineering Co., Inc.– YELLOW JACKET Products Division

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Ice Buildup on Evaporator Ice buildup acts as insulation –Prevents heat from being transferred –Evaporator may not be able to provide cooling Possible causes –Faulty gasket –Mullion heater failure –Faulty defrost feature

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Faulty Gasket Gasket forms poor seal in just one location –Use heat gun to heat and reform –Apply silicone grease to help seal Signs that gasket should be replaced –Increased system running time –Condensation or mold on gasket –Slip of paper in door can be pulled out easily

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Replacing a Gasket Use gasket specific to model or universal repair kit Place new gasket in warm water while removing old gasket Loosen screws and remove old gasket Insert new gasket and tighten screws Realign door if needed Sealed Unit Parts Co., Inc.

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Other System Failures Mullion heater failure –Electric heater around door opening that prevents condensation –If not working, moisture or ice may prevent the door from closing properly –Moisture in air enters and collects on evaporator Automatic defrost system failure –Automatic defrost system should prevent excessive evaporator frosting –Ice buildup may indicate defrost system is not working properly

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Manual Defrost Unplug unit Store contents in cooler or other refrigerator Prop doors open to thaw frost Acceleration methods –Large pot of hot water –Hair dryer or heat gun Remove accumulated water Wash with baking soda and water Dry before returning to operation

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Caution Never use a sharp object to remove ice from evaporator. Doing so may puncture the evaporator.

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Moisture and Ice in Cabinet Insulation Presence of moisture means air has leaked in through the outer shell Insulation becomes wet and ineffective Two common results –Condensing unit runs more often –Outside surface of refrigerator feels colder Fix by finding and sealing the leak

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Troubleshooting Ice Makers Check connection to water and electric power Check temperature of freezer compartment Make sure several cycles have run and ice maker is in freezing phase Make sure thermostat is single-throw switch wired in series with mold heater Maytag

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Troubleshooting Ice Makers (cont.) Check ejector blades –Two revolutions per cycle –Ice is not stored on blades after harvest Make sure water valve solenoid is wired in series with mold heater Maytag

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Sources of Unusual Noises Loose baffles or ducts Tubing touching something that vibrates Listing of condensing unit Fan and motor vibration Loose components or panels Loosely stored articles Shelves not seated properly Amprobe

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Detecting and Reducing Unusual Noises Use ultrasonic leak detector –Detects sounds made by leaks Noises from compressor –Check for overload Reduce noise caused by vibrating tubing Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Unusual Cycling Times Cycle times depend on –Amount of storage space being used –Temperature outside cabinet –Compressor condition –Temperature of contents added to cabinet –Humidity of air entering the cabinet Common duty cycle: one-third of the time Unusual or unexpected changes –Investigate immediately –May indicate system trouble

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. System Failure Failure types –Compressor runs, but cabinet temperature is incorrect –Compressor does not run –Compressor runs erratically Check external components and conditions before diagnosing and replacing internal components Eliminate other possible causes of failure before replacing a compressor

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Checking External Circuits Wiring and Auxiliary System Problems –Power-in connections –Thermostat –Wire terminals –Relays –Compressor capacitors –Defrost timer Check ground wire connections Check switches along the hot wire Use multimeter and test cord

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Defrost Timer Wiring Diagram Frigidaire

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Checking Compressor Failure Check electricity to compressor Check starting relay and circuit protectors Disconnect all wiring from compressor Check compressor with manual start test cord Goodheart-Willcox Publisher Test Cord for a Compressor with a Split-Phase Motor

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Test Cord Variations Test Cord for a Compressor with a Capacitor-Start, Induction-Run (CSIR) Motor Test Cord for a Compressor with a Capacitor-Start, Capacitor-Run (CSCR) Motor Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Safety After testing a compressor, short the compressor capacitor using a 20 k , 2 W resistor. This will eliminate the possibility of electrical shock.

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Analyzing Pressure-Temperature Conditions Before servicing a system, know its normal operating cycle values –Temperature in evaporator –Low-side pressure –Temperature of condenser –High-side pressure Use a data logger to record operating temperatures and pressures over time

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Typical Refrigerator Operating Conditions Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Uses of Service Valves on Hermetic Systems Check internal pressures Recover or add refrigerant Add oil Evacuate the system When replacing filter-driers, compressors, evaporators, and metering devices Recharge system

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hermetic Systems with Valve Adapters Valve adapter –Fastens to compressor dome –Removable valve stem attaches to valve Allows connection of gauges and charging cylinders Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Process Tube and Adapters Process tube –Small length of tube through compressor housing –Allows evacuation, testing, and charging during assembly Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Pinch-Off Tool Isolates parts of tubing in emergency Use only when absolutely necessary Ritchie Engineering Co., Inc. – YELLOW JACKET Products Division

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Effect of Altitude on Refrigerator Temperatures Atmospheric pressure reduces as elevation increases –Sensing bulb thermostat may run too cold above 5000 –Does not affect bimetal and electronic thermostats Use altitude adjustment to set thermostat Amana Refrigeration, Inc.

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Common Problems Restrictions Moisture in refrigerant coil Wax Shortage of refrigerant Components that frequently cause trouble –Compressor –Filter-drier –Capillary tubes –Post-condenser loop –Electric defrost heater –Hot-gas defrosting valve

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Locating Compressor Faults Disconnect power to unit Clean outside of compressor dome Disconnect system wiring from compressor Use ohmmeter to check for continuity, shorts, and grounds Connect a test cord –If system starts, problem is external

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Compressor Checks Check volt-ampere (watt) reading at normal low-side and high-side pressures –If reading is below rating, pump may be worn out If operating correctly but not building up pressure –Check for internal problems Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Diagnosing Capillary Tube Problems Check for correct tube size Check amount of refrigerant in system Check for restrictions or clogs –Replace clogged filter-drier –Replace blocked capillary tube –Address any other blocks Goodheart-Willcox Publisher

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Other Component Problems Post-condenser loop problems –Isolate loop from rest of system –Attach access valve –Place nitrogen charge in loop If pressure drops, loop is leaking Electric resistance defrost problems –If ice builds up on evaporator Check evaporator fan Check defrost system Inspect and test defrost resistance wire

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hot-Gas Defrost Problems Hot-gas valve stuck open or closed –Open: only defrosts, no refrigeration –Closed: not able to defrost at all Evaporator overloaded with ice –Solenoid’s electric coil may have failed (valve closed) –Timer may not be working correctly –Stuck valve stem in solenoid

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hot-Gas Defrost Problems (cont.) Evaporator not cooling –Strike valve to loosen and close valve (during normal refrigeration cycle, while defrost is off) –If evaporator does not begin cooling, replace the solenoid valve

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hot-Gas Defrost Problems (cont.) Evaporator not cooling –Strike valve to loosen and close valve (during normal refrigeration cycle, while defrost is off) –If evaporator does not begin cooling, replace the solenoid valve

Copyright Goodheart-Willcox Co., Inc. May not be posted to a publicly accessible website. Hot-Gas Defrost System Goodheart-Willcox Publisher