Lesson 1Parts Selection an' Sourcing: Identifyin' OEM vs Compatible Parts, Readin' Part Numbers an' Spec SheetsDevelop skills fi identify correct replacement parts usin' model tags, OEM catalogs, an' spec sheets, compare OEM an' aftermarket options, verify electrical an' mechanical compatibility, an' avoid common orderin' an' substitution mistakes dat can cause problems later.
Locating and decoding appliance model tagsReading OEM part numbers and revisionsUsing exploded views and parts diagramsComparing OEM and aftermarket componentsVerifying electrical and mechanical compatibilityLesson 2Compressor an' Relay Testin': Start Relay/Capacitor Diagnosis, Amp Draw Testin', Locked Rotor IdentificationLearn how fi test fridge compressors an' start components usin' meters an' clamp ammeters, identify failed relays an' capacitors, recognize locked-rotor conditions, an' decide when a compressor is electrically or mechanically beyond repair fi save time an' money.
Identifying compressor terminals and winding layoutTesting PTC and mechanical start relaysStart and run capacitor inspection and testsMeasuring compressor amp draw and LRADiagnosing locked rotor and internal shortsLesson 3Customer Communication Scripts: Simple Explanation of Cause, Recommended Repairs vs Replacement, Cost/Benefit an' Maintenance Tips fi Prevent RecurrenceBuild clear, professional communication habits wid customers by explainin' faults in simple language, presentin' repair versus replacement options, estimatin' costs, an' offerin' maintenance tips dat reduce future breakdowns an' callbacks in yuh daily work.
Explaining diagnosis in non-technical termsDiscussing repair versus replacement choicesPresenting written estimates and optionsSetting realistic timelines and outcomesProviding preventive maintenance adviceLesson 4Electrical an' Sensor Tests: Multimeter Checks fi Continuity/Resistance of Defrost Heater, Thermistor Testin', Fan Motor Current DrawPractice safe electrical diagnostics usin' a multimeter an' clamp meter fi check continuity, resistance, an' current draw on defrost heaters, thermistors, fan motors, an' wirin', distinguishin' normal readings from open, shorted, or driftin' components fi accurate fixes.
Multimeter safety and test lead setupContinuity and resistance checks on heatersThermistor resistance versus temperature chartsFan motor voltage and current measurementsTesting door switches and harness connectionsLesson 5Interpretin' Symptoms: Warm Fresh Food, Cold Freezer wid Back-Wall Ice, Continuous Compressor OperationLearn fi interpret common fridge symptoms such as warm fresh food, icy back walls, noisy or continuous runnin', an' intermittent coolin', den map each pattern to likely airflow, defrost, control, or sealed system issues fi quick diagnosis.
Warm fresh food, normal freezer analysisBack-wall ice and airflow restriction cluesContinuous or near-continuous run-timeShort cycling and frequent startsNoises, vibrations, and rattlesIntermittent cooling and nuisance tripsLesson 6Common Faults: Compressor, Evaporator Frost/Defrost System, Evaporator Fan, Temperature Sensors, Thermostats, an' Refrigerant LeaksConnect typical fridge symptoms to likely failed components, includin' compressor problems, evaporator frost issues, fan failures, sensor errors, an' refrigerant leaks, an' learn fi prioritize tests dat confirm or rule out each suspected fault efficiently.
No cool or warm cabinet in both sectionsWarm fresh food, cold or icy freezerShort cycling and long run-time issuesNoisy operation and vibration complaintsIntermittent cooling and nuisance tripsSigns suggesting sealed system leaksLesson 7Thermodynamics of Domestic Refrigeration Systems an' Airflow PatternsUnderstand how heat moves in domestic fridges, includin' pressure–temperature relationships, evaporator an' condenser roles, an' cabinet airflow patterns, so yuh can link poor coolin', icin', an' short cyclin' to specific thermodynamic faults wid confidence.
Basic refrigeration cycle and key componentsPressure–temperature relationship in systemsEvaporator loading and frost formationCondenser heat rejection and ambient effectsAirflow paths in fresh food and freezerImpact of door openings and loadingLesson 8Repair Procedures: Replacin' Defrost Heater, Thermistor, Evaporator Fan, Door Gasket; Steps fi Recover/Recharge Refrigerant (Scope an' Contractor Decision)Study step-by-step repair procedures fi common failures, includin' replacin' defrost heaters, thermistors, evaporator fans, an' door gaskets, an' understand when refrigerant recovery or recharge must be referred to licensed contractors fi safety.
Safe disassembly and panel removalReplacing defrost heaters and wiringThermistor access, testing, and replacementEvaporator and condenser fan replacementDoor gasket removal and installationScope limits for sealed system repairsLesson 9Safety Procedures: Electrical Isolation, Refrigerant Handlin' Regs, PPE, Pressure Relief an' Recovery BasicsApply essential safety practices fi fridge service, includin' electrical isolation, lockout habits, PPE selection, safe handlin' of sharp metal an' movin' parts, an' understandin' basic refrigerant safety an' regulatory responsibilities every time.
Lockout, tagout, and unplugging routinesVerifying absence of voltage before workPPE for electrical and sharp-edge hazardsSafe handling of fans and moving partsBasics of refrigerant exposure risksRecordkeeping and regulatory dutiesLesson 10Defrost System Diagnostic Plan: Timer, Bi-Metal/Thermostat, Defrost Heater, Control Board ChecksFollow a stepwise plan fi diagnose defrost system faults by testin' timers or control boards, defrost heaters, bi-metal thermostats, an' sensors, distinguishin' between electrical failures an' control logic issues dat cause evaporator icin'.
Recognizing symptoms of defrost failureLocating defrost components by designTesting defrost heaters for continuityChecking bi-metal and defrost thermostatsForcing defrost mode from control boardInterpreting timer and control board faultsLesson 11Visual Inspection Checklist: Seals, Door Alignment, Ice Buildup, Drain an' Defrost Heater AreasUse a structured visual checklist fi quickly spot common fridge issues, includin' gasket leaks, door misalignment, ice buildup, blocked drains, damaged wirin', an' dirty condensers, reducin' callbacks an' guidin' deeper diagnostic testin'.
Inspecting door gaskets and sealing surfacesChecking door alignment and hinge wearIdentifying ice buildup and airflow blockagesExamining drain pan, tube, and outletsInspecting wiring, connectors, and insulationLesson 12Refrigerant System Checks: Static Pressure Readings, Leak Detection Methods, When fi Call Certified Refrigerant TechnicianLearn how fi perform basic sealed system checks within legal limits, includin' static an' runnin' pressure readings, temperature split observations, simple leak detection methods, an' recognizin' when fi stop an' call a certified refrigerant technician.
Recognizing sealed system componentsSafe use of service ports and gaugesStatic and running pressure interpretationTemperature split and line frost patternsNon-invasive leak detection techniquesWhen to involve certified techniciansLesson 13Post-Repair Tests an' Verification: Temperature Stabilization Testin', Run-Time Monitorin', Sealin' an' Airflow ValidationVerify successful repairs by monitorin' cabinet temperatures, run-time, an' defrost performance, checkin' door seals an' airflow, an' documentin' readings so yuh can confidently close di job an' reduce di risk of callbacks or repeat failures.
Stabilization time and temperature loggingChecking thermostat and sensor responseMonitoring compressor and fan run-timeVerifying door seal and light operationConfirming defrost cycle performanceFinal documentation and customer sign-off
