GA HVAC study guide
GA HVAC · Work through your exam, one topic at a time.
The Georgia Conditioned Air Contractor license is the state credential that authorizes a business to install, alter, service, and repair heating, ventilating, and air-conditioning systems for the public in Georgia. It is issued at the company level, so the qualifying individual typically pairs a trade examination with a separate business-and-law examination before a firm can be licensed to contract for conditioned air work. The GA HVAC study guide has 10 sections and about 3,133 words.
01HVAC System Design, Load Calculation, and Equipment Selection
Every defensible design begins with a room-by-room load calculation. Heating load is dominated by envelope conduction (Q = U × A × ΔT) plus infiltration and ventilation; cooling load adds solar and internal gains and splits into sensible and latent components.
339 words, about 2 min02Refrigeration Cycle, Components, and Refrigerants
The vapor-compression cycle has four steps: compression (low-pressure vapor to high-pressure vapor), condensation (rejecting heat at saturated condensing temperature), expansion through a metering device, and evaporation (absorbing heat at saturated evaporating temperature). The compressor raises pressure, not temperature directly - temperature follows the refrigerant's pressure-temperature relationship.
300 words, about 2 min03Heating Equipment and Systems (Furnaces, Boilers, Heat Pumps)
Gas furnaces are rated by AFUE, which accounts for cycling and jacket losses, not just steady-state combustion efficiency. Condensing units recover latent heat (category IV venting, plastic flue, acidic condensate with a trap and neutralizer); non-condensing units (category I) need a properly sized chimney with draft and cannot be sidewall vented without a listed kit.
311 words, about 2 min04Air Distribution, Ductwork, and Ventilation
A duct system is a budget problem. Start with the blower's rated external static pressure, subtract every component drop (filter, coil, dampers, heat strips, grilles), and the remainder is available static pressure for the ductwork.
306 words, about 2 min05Piping, Fittings, and Fuel Gas Systems
Refrigerant piping must be sized for pressure drop and oil return. Use ACR copper, braze with a nitrogen purge to prevent internal oxidation, and protect adjacent surfaces.
328 words, about 2 min06Electrical Power, Motors, and HVAC Controls
Most HVAC electrical troubleshooting happens on the 24-volt control circuit. Know Ohm's law (E = I × R), the difference between a series safety switch and a parallel load, and how to read a ladder diagram: power flows from the transformer through the thermostat and safeties to the contactor coil.
319 words, about 2 min07Installation, Start-up, and Commissioning
Good installation starts with clearances, structural support, condensate slope, service access, and routing that respects manufacturer limits on line-set length and elevation. Electrical, gas, and condensate connections must match the listing and the code.
288 words, about 1 min08Testing, Adjusting, and Balancing (TAB)
Balancing sets design airflows and water flows, then proves them. Instruments include the balancing hood at grilles, pitot tube with a manometer for duct traverses, anemometers, tachometers, and pressure gauges.
333 words, about 2 min09Maintenance, Troubleshooting, and Repair
Preventive maintenance prevents most failures: filters, belts and tension, bearings, coil cleaning, condensate drains and traps, electrical connections and contactor pitting, refrigerant charge verification, and combustion analysis with CO testing on fuel-fired equipment. Record baseline readings so future comparisons are meaningful.
289 words, about 1 min10Codes, Standards, Permits, and Jobsite Safety
Codes set minimums; manufacturer listings and instructions set specifics. When they conflict, follow the more restrictive requirement, and never install equipment in a way that violates its listing.
320 words, about 2 min