Lesson 1Parts selection and sourcing: identifying OEM vs compatible parts, reading part numbers and spec sheetsBuild skills to pick correct replacement parts using model labels, OEM lists, and spec papers, compare original and market options, check electrical and mechanical fit, and dodge common buying and swap errors.
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 and relay testing: start relay/capacitor diagnosis, amp draw testing, locked rotor identificationLearn to test fridge compressors and start parts with meters and clamp tools, spot bad relays and capacitors, know locked-rotor issues, and decide when a compressor is bad electrically or mechanically beyond fix.
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 and maintenance tips to prevent recurrenceBuild clear, professional talk habits with customers by explaining faults in easy words, showing repair against new buy options, guessing costs, and giving upkeep tips that cut future breaks and call-backs.
Explaining diagnosis in non-technical termsDiscussing repair versus replacement choicesPresenting written estimates and optionsSetting realistic timelines and outcomesProviding preventive maintenance adviceLesson 4Electrical and sensor tests: multimeter checks for continuity/resistance of defrost heater, thermistor testing, fan motor current drawPractice safe electrical checks using multimeter and clamp meter to test continuity, resistance, and current on defrost heaters, thermistors, fan motors, and wires, telling normal from open, short, or off parts.
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 5Interpreting symptoms: warm fresh food, cold freezer with back-wall ice, continuous compressor operationLearn to read common fridge signs like warm fresh side, icy back walls, noisy or non-stop run, and on-off cooling, then link each to likely air flow, defrost, control, or sealed system problems.
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, and refrigerant leaksLink usual fridge signs to likely bad parts, including compressor issues, evaporator frost problems, fan breaks, sensor errors, and gas leaks, and learn to rank tests that confirm or rule out each suspected fault.
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 and airflow patternsUnderstand how heat moves in home fridges, including pressure-temperature links, evaporator and condenser jobs, and cabinet air flows, so you can tie poor cooling, icing, and short runs to specific heat faults.
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: replacing defrost heater, thermistor, evaporator fan, door gasket; steps to recover/recharge refrigerant (scope and contractor decision)Study step-by-step fix methods for common breaks, including swapping defrost heaters, thermistors, evaporator fans, and door seals, and know when gas recovery or refill needs licensed experts.
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 handling regs, PPE, pressure relief and recovery basicsApply key safety ways for fridge service, including electrical cut-off, lockout habits, PPE pick, safe handle of sharp metal and moving parts, and basic gas safety and rule duties.
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 step plan to diagnose defrost faults by testing timers or control boards, defrost heaters, bi-metal thermostats, and sensors, telling electrical breaks from control logic issues causing evaporator ice.
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 and defrost heater areasUse a planned visual list to quickly spot common fridge issues, including seal leaks, door off-line, ice build, blocked drains, damaged wires, and dirty condensers, cutting call-backs and guiding deeper tests.
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 to call certified refrigerant technicianLearn to do basic sealed system checks within law limits, including static and run pressure reads, temperature split watches, simple leak finds, and know when to stop and call certified gas tech.
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 and verification: temperature stabilization testing, run-time monitoring, sealing and airflow validationCheck successful fixes by watching cabinet temps, run-time, and defrost work, testing door seals and air flow, and noting reads so you can close the job sure and cut call-back or repeat break risks.
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