AC Fridge Repairing Course

Lesson 1 • The Vapour Compression Cycle

Traces refrigerant through all four cycle stages: compression, condensation, expansion, evaporation. Builds the mental model used throughout the course.

Lesson 2 • Refrigerant Safety and Handling

Covers refrigerant toxicity, flammability classes, and proper recovery procedures per environmental regulations. Prepares learners for compliant field work.

Lesson 3 • Basic Thermodynamics for Technicians

Covers heat transfer modes, latent vs. sensible heat, and the refrigeration effect. Anchors all subsequent component and cycle analysis.

Lesson 4 • Tools and Test Equipment Overview

Identifies hand tools, manifold gauge sets, multimeters, and leak detectors used throughout the course. Learners match each tool to its diagnostic purpose.

Lesson 1 • Expansion Devices

Covers capillary tubes, thermostatic expansion valves, and electronic expansion valves. Learners select the correct device for a given system configuration.

Lesson 2 • Electrical Components and Controls

Identifies thermostats, start relays, overload protectors, capacitors, and fan motors. Links each component to its role in system start-up and protection.

Lesson 3 • Condensers and Evaporators

Distinguishes air-cooled and wire-on-tube condenser designs and frost-free vs. static evaporators. Explains how coil condition affects system performance.

Lesson 4 • Compressor Types and Functions

Examines reciprocating, rotary, and scroll compressors found in domestic appliances. Connects compressor type to expected performance and failure modes.

Lesson 1 • AC Unit Wiring and PCB Layouts

Covers split AC indoor/outdoor unit wiring, PCB terminal identification, and communication signal lines. Learners connect diagrams to physical board inspection.

Lesson 2 • Pictorial Wiring Diagrams

Teaches how to read colour-coded pictorial diagrams showing physical wire routing. Bridges the gap between schematic logic and actual appliance wiring.

Lesson 3 • Ladder Diagram Interpretation

Explains power rails, rungs, and load placement in ladder logic. Learners trace current paths to determine which components energise under given conditions.

Lesson 4 • Defrost and Control Circuit Analysis

Focuses on defrost timers, defrost heaters, and thermistor-based control circuits common in frost-free refrigerators. Prepares learners for defrost fault diagnosis.

Lesson 1 • Symptom-Based Diagnostic Approach

Introduces a structured symptom-to-cause diagnostic framework. Prevents random part replacement by teaching logical elimination of fault possibilities.

Lesson 2 • Interpreting Error Codes and Sensors

Decodes manufacturer error codes and tests thermistors, pressure switches, and flow sensors. Connects sensor data to control board fault logic.

Lesson 3 • Refrigerant Leak Detection

Applies electronic detectors, UV dye, and soap bubble methods to locate leaks. Learners select the appropriate method based on system type and leak severity.

Lesson 4 • Manifold Gauge Set Diagnostics

Teaches correct gauge connection, reading high/low side pressures, and interpreting abnormal pressure patterns. Links pressure readings to specific system faults.

Lesson 1 • Door Gasket and Mechanical Repairs

Addresses gasket replacement, door alignment, condenser fan motor swap, and drain line clearing. Covers high-frequency low-complexity repairs that maximise shop throughput.

Lesson 2 • Thermostat and Control Board Repair

Guides replacement of mechanical thermostats and electronic control boards with correct calibration. Ensures accurate temperature control post-repair.

Lesson 3 • Compressor Replacement Procedure

Details safe refrigerant recovery, compressor removal, and installation with correct oil charge. Learners perform a complete swap on a practice unit.

Lesson 4 • Sealed System Leak Repair

Teaches brazing techniques, leak repair on copper tubing, and recharging the sealed system. Learners practise on scrap tubing before live system work.

Lesson 1 • Capacitor and Relay Replacement

Identifies failed run/start capacitors and relays as the most common window AC electrical fault. Learners test, source, and replace components correctly.

Lesson 2 • Cleaning, Reassembly, and Testing

Details coil cleaning, drain pan treatment, reassembly torque sequence, and final performance test. Ensures unit leaves the shop in optimal condition.

Lesson 3 • Fan Motor and Blade Service

Covers dual-shaft fan motor testing, blade removal, and motor replacement. Correct blade pitch and balance prevent vibration and noise complaints.

Lesson 4 • Window AC Disassembly and Inspection

Covers safe removal from wall sleeve, panel disassembly sequence, and initial inspection checklist. Establishes correct disassembly habits before any repair.

Lesson 1 • Indoor Unit Repairs

Covers blower wheel cleaning, evaporator coil leak repair, drain pump replacement, and louver motor service. Addresses the most frequent indoor unit complaints.

Lesson 2 • Line Set Installation and Leak Testing

Teaches flaring, brazing, and pressure testing refrigerant line sets for new installations and repairs. Correct line set work prevents future refrigerant loss.

Lesson 3 • Split System Architecture Review

Maps refrigerant and electrical connections between indoor and outdoor units. Establishes the system-level view needed before component-level repair.

Lesson 4 • Inverter Compressor Diagnostics

Explains variable-frequency drive operation and inverter board testing. Learners distinguish inverter faults from compressor mechanical failures.

Lesson 1 • Intermittent Fault Diagnosis

Addresses faults that appear only under specific load or temperature conditions. Learners use data logging and stress testing to reproduce and confirm intermittent failures.

Lesson 2 • Multi-Fault and Cascade Failures

Teaches recognition of cascade failures where one fault damages secondary components. Learners avoid incomplete repairs that return as repeat callbacks.

Lesson 3 • Preventive Maintenance Procedures

Defines scheduled maintenance tasks that extend appliance life and reduce emergency calls. Learners build a maintenance service offering for recurring revenue.

Lesson 4 • Repair Documentation and Warranty

Covers job card completion, parts traceability, and warranty claim documentation. Protects the technician and business from liability disputes.