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course outline

Safety and First Aid in the Workshop
- Workshop rules and regulations
- Safety devices/equipment
- Safety devices/equipment - Identification and operation of various types of fire extinguishers
- Accident: causes and prevention techniques
- First Aid materials
- Application of first aid materials
Energy, Matter and Power
- Energy - Definition of energy
- Energy - The process of energy conversion (electrical to mechanical, gas to vapour, mechanical to heat)
- Energy - Demonstration of conversion of mechanical to heat energy (e.g., rubbing of palms)
- Energy - Meaning of internal energy
- Energy - Enthalpy of a fluid substance, its pressure, volume, and temperature of internal energy
- Nature of matter - The p-h diagram of refrigerant
- Nature of matter - State of matter (solid, liquid, gas or vapour)
- Nature of matter - Demonstrate the conversion of ice block to water
- Power - Change of state of matter
- Power - The meaning of power
- Power - Calculation of power used by a compressor
- Power - Unit of power: watts and kilowatts; unit of heat: joules and kilojoules
Temperature and Pressure
- Temperature and its measurement - Concept of temperature
- Temperature and its measurement - Different types of thermometer (gas, resistance, liquid, and thermocouple)
- Temperature and its measurement - Temperature scale conversion (Centigrade to Fahrenheit, Celsius to Kelvin, Fahrenheit to Rankine)
- Temperature and its measurement - International practical temperature (boiling point of oxygen, triple point of water, boiling point of water)
- Pressure and its measurement - Concept of pressure
- Pressure and its measurement - Different types of pressure measuring devices (barometer, manometer, Bourdon tube gauge)
- Pressure and its measurement - Demonstration of the use of a barometer
- Pressure and its measurement - Pressure measurement
- Pressure and its measurement - Uses of suction and high pressure gauges
- Pressure and its measurement - Demonstrate how suction and high pressure gauges are used to determine refrigerant performance
- Pressure and its measurement - Effects of temperature, pressure and volume in refrigeration and air conditioning systems
- Pressure and its measurement - Gas laws (Boyle's law, Charles' law, and Dalton's law)
- Pressure and its measurement - Calculations involving general gas law formulae
- Pressure and its measurement - Plotting various temperature scales
Refrigeration and Air Conditioning Systems
- Introduction to refrigeration - Refrigeration cycle (Evaporation, compression, condensation, and expansion)
- Introduction to refrigeration - Layout diagram of refrigeration systems
- Introduction to refrigeration - Types and applications of the various forms of refrigeration
- Introduction to refrigeration - Principles of operation of forms of refrigeration system
- Introduction to refrigeration - Functions of components and accessories (relay, solenoid valves, capacitors, and thermostat)
- Refrigerants - Definition and types of refrigerants
- Refrigerants - Identification of refrigerant by cylinder colours
- Refrigerants - Chemical names and formulae
- Refrigerants - Properties and uses of refrigerants
- Refrigerants - Refrigerant flow controls (TEV, AEV, capillary tube)
- Refrigerants - Operations of refrigerant flow controls
- Air-Conditioning processes - Psychometric properties of air
- Air-Conditioning processes - Demonstration of air conditioning principle by sling psychometer
- Air-Conditioning processes - The processes of air conditioning: heating and cooling
- Air-Conditioning processes - Latent and sensible heat, saturated and super-saturated vapour
- Air-Conditioning processes - Demonstration of the difference between latent and sensible heat by use of methylated spirit on human skin
Compressors, Condensers and Evaporators
- Compressors - Types of compressors
- Compressors - Construction of compressors
- Compressors - Working principles of compressors
- Condensers - Construction of condensers
- Condensers - Demonstrate how to service a condenser
- Condensers - Calculation of heat load on condensers
- Condensers - Types and functions of liquid receiver and service valves
- Condensers - Principle of operation of liquid receiver and service valves
- Evaporators - Types of evaporators
- Evaporators - Construction and services of evaporators
- Evaporators - Demonstrate how to service evaporators
- Evaporators - Working principles of evaporators
- Evaporators - Heat load estimates on evaporators
Workshop Practices
- Basic tools used in refrigeration and air-conditioning workshops
- Tools and procedures for servicing window unit air-conditioner
- Servicing of a window air-conditioner
- Fault diagnosis and trouble shooting - Different methods (systematic and observation)
- Fault diagnosis and trouble shooting - Common faults in refrigeration systems and their symptoms (leakage, faulty units, faulty compressor, poor cooling, current leakage)
- Maintenance and Testing - Techniques of effective repairs in refrigeration and air-conditioning systems
- Maintenance and Testing - Techniques of trouble shooting in a given system
- Maintenance and Testing - Testing for leakages, polarity, insulation continuity, pressure and efficiency
- Maintenance and Testing - Demonstrate how to test for leakages, polarity continuity and efficiency
- Maintenance and Testing - Maintenance of compressors, evaporators, motors, condensers, valves, accumulators and contactors
- Maintenance and Testing - Demonstrate how to repair faults in compressors, evaporators, motor and condensers
Installation Processes
- Piping, Ducting and Trunking - Concept of piping, ducting and trunking
- Piping, Ducting and Trunking - Piping a condenser and an evaporator
- Piping, Ducting and Trunking - Ducting, trunking and installation of air-conditioners
- Piping, Ducting and Trunking - Installation of a split air-conditioner
- Piping, Ducting and Trunking - Tools (mallet hammer, flaring tools, silver tape, dot-punch, bending spring, amaflex, hacksaw, PVC pipes)
- Motors and generators - Types, functions, operations and application
- Motors and generators - Installation procedures
- Motors and generators - Maintenance in a refrigeration system
- Motors and generators - Servicing
- Cold room - Working principles
- Cold room - Installation procedures
- Cold room - Factors affecting operations
Insulation Processes
- Importance of insulation of refrigeration and air-conditioning systems
- Types of insulating materials
- Functions and properties of insulation materials
- Procedure for insulating refrigeration and air-conditioning systems
Entrepreneurship
- Business concept - Business enterprise and types of businesses (sole proprietorship, partnership, limited liability)
- Marketing - Sources of finance (loan, mortgage, shares, overdrafts, savings)
- Marketing - Types and functions of marketing styles
- Marketing - Meaningful marketing at the least cost
- Marketing - Carry out a commercial marketing survey to set up refrigeration and air-conditioning business
- Marketing - Marketing protocol and cost
- Accounting - Principles of Accounting
- Accounting - The concept of business as a separate entity
- Accounting - Ledger, trial balance and balance sheet
- Accounting - Preparation of ledger and balance sheet

Topics

Safety devices/equipment
Includes helmet, goggles, safety boots, hand gloves, overall, apron, sand bag, fire extinguishers.

Air Conditioning

WAEC WASSCE

course outline

Topics

Safety devices/equipment