AZ HVAC study guide
AZ HVAC · Work through your exam, one topic at a time.
The Arizona C-39 Air Conditioning and Refrigeration license is a contractor license issued by the Arizona Registrar of Contractors (ROC). It authorizes a business - not an individual technician - to contract for the installation, alteration, repair, and servicing of heating, ventilating, air conditioning, and refrigeration systems in Arizona. The AZ HVAC study guide has 9 sections and about 3,162 words.
01Arizona Statutes, Rules, and Contractor Licensing
Air conditioning and refrigeration contracting in Arizona is regulated by the Registrar of Contractors (ROC). The core classifications are R-39 (residential), C-39 (commercial), and CR-39 (dual).
376 words, about 2 min02Refrigeration Theory, Refrigerants, and System Components
Every system is four components in a loop: evaporator, compressor, condenser, and metering device. Refrigerant boils in the evaporator at low pressure, absorbing heat; the compressor raises pressure and temperature; the condenser rejects heat and condenses the refrigerant; the metering device drops pressure back to evaporator conditions.
363 words, about 2 min03HVAC Equipment: Heating, Cooling, and Ventilation Units
Know the difference between split systems (outdoor condensing unit plus indoor coil), packaged units (all components in one cabinet with supply and return ducts), and mini-split/VRF systems. Heat pumps add a reversing valve, defrost control, and auxiliary or emergency electric resistance heat.
352 words, about 2 min04Electrical Systems, Motors, and Controls
Ohm's law and power relationships drive every electrical question. Single-phase power in watts equals volts times amps times power factor.
356 words, about 2 min05Ductwork, Air Distribution, and Ventilation
Air moves because of pressure difference, and the fan must overcome the total external static pressure of the system. A typical residential budget is about 0.5 in.
364 words, about 2 min06Piping, Tubing, Brazing, and Soldering
Refrigerant lines use ACR copper, which is cleaned and capped; types L and K are used for water and gas piping. Soft soldering with tin-antimony or lead-free solder is for potable water and low-temperature work, never for refrigerant lines.
348 words, about 2 min07Load Calculation, System Sizing, and Design Principles
A load calculation, commonly Manual J for residential, totals sensible and latent gains and losses: conduction through walls, ceilings, floors, and windows (U times area times temperature difference), solar gain through glass (a function of orientation, shading, and solar heat gain coefficient), internal gains from people, lights, and appliances, and infiltration plus mechanical ventilation. Then equipment is selected with Manual S and ducts designed with Manual D.
332 words, about 2 min08Jobsite and Occupational Safety
HVAC work combines electrical, refrigerant, combustion, pressure, chemical, and fall hazards. The exam expects you to recognize hazard classes and the administrative control that answers each: lockout/tagout for electrical and rotating equipment, personal protective equipment for eyes, hands, and hearing, confined space procedures for crawl spaces and vaults, and fall protection for elevated work.
342 words, about 2 min09Business Management, Estimating, and Project Administration
A bid is built from material takeoff, labor units, equipment, subcontractors, permits, and general conditions, then burdened with overhead and profit. Markup on cost and margin on price are different numbers, and that difference is the classic exam trap.
329 words, about 2 min