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Paths · Foundations

HVAC Technician from Zero

The whole arc: how the machine works, the air side, the refrigerants, and then the certifications that make you employable. Take it in order; every section assumes the one before.

49 steps

How the machine works

  1. 1Heat Transfer Basics
  2. 2Pressure-Temperature Relationships
  3. 3How the Refrigeration Cycle Works
  4. 4Compressors
  5. 5Condensers
  6. 6Metering Devices and TXVs
  7. 7Evaporators
  8. 8How Superheat Works
  9. 9How Subcooling Works

The air side

  1. 10Airflow Fundamentals
  2. 11Psychrometrics
  3. 12Static Pressure
  4. 13Duct Design Basics

Refrigerants

  1. 14Refrigerant Types and Designations
  2. 15Refrigerant Oils
  3. 16Refrigerant Safety and Handling
  4. 17The A2L Transition: R-410A to R-32 and R-454B

Electrical for HVAC

  1. 18Electrical Fundamentals for HVAC
  2. 19Capacitors in HVAC
  3. 20HVAC Motors: PSC, ECM and Beyond
  4. 21Reading HVAC Schematics
  5. 22Contactors and Relays
  6. 23Control Board Diagnostics
  7. 24Defrost Controls
  8. 25Thermostats and Low-Voltage Controls

The equipment you'll work on

  1. 26Split System Air Conditioners
  2. 27How Heat Pumps Work
  3. 28Ductless Mini-Splits
  4. 29Packaged Units and RTUs
  5. 30Gas Furnaces
  6. 31Furnace Sequence of Operation
  7. 32Electric Heat
  8. 33Combustion Analysis
  9. 34Commercial Refrigeration Systems
  10. 35Ice Machines

Service skills

  1. 36Brazing for HVAC
  2. 37Gauges and Manifolds
  3. 38Evacuation and Vacuum
  4. 39Charging by Superheat and Subcooling
  5. 40Refrigerant Recovery
  6. 41Leak Detection
  7. 42A Diagnostic Method That Works
  8. 43Diagnosing Airflow Problems
  9. 44Diagnosing Electrical Problems
  10. 45Diagnosing Refrigerant Circuit Problems

Get certified

  1. 46EPA 608: What It Is and Why It Exists
  2. 47EPA 608 Universal: The Proctored Path
  3. 48NATE Certification Explained
  4. 49The CHP-5 Pathway: Five Exams, Five Domains