CT HVAC study guide
CT HVAC · Work through your exam, one topic at a time.
HVAC Excellence is the HVACR education-and-workforce arm of ESCO Group, based in Mt. Its stated mission is to develop standards and resources that strengthen the quality of education, training, credentialing, and workforce development across the HVACR and building-science industries. The CT HVAC study guide has 8 sections and about 2,351 words.
01Safety and Environmental Protection
Safety questions test judgment as much as facts. You must know PPE selection (safety glasses, gloves, respirator), lockout/tagout of electrical and stored energy, arc-flash boundaries, and the physical hazards of refrigerants: frostbite from liquid contact, oxygen displacement in low-lying spaces, and decomposition products when refrigerant meets an open flame.
315 words, about 2 min02Tools, Instruments, and Measurement
Candidates should match the instrument to the measurement and recognize its limits. Manifold gauges read high-side and low-side pressure; a micron gauge reads vacuum depth; an electronic manometer reads duct static in inches of water column; a thermocouple or clamp-on thermometer reads line temperature; an anemometer or velometer reads air velocity; a sling or digital psychrometer reads dry-bulb and wet-bulb; a clamp meter reads current; a multimeter reads voltage, resistance, and continuity.
309 words, about 2 min03Refrigeration Fundamentals and the Refrigeration Cycle
You must be able to trace the four legs of the cycle and explain what each component does. The compressor raises pressure and temperature; the condenser rejects sensible and latent heat and leaves liquid; the metering device drops pressure and creates a low-temperature mixture; the evaporator absorbs heat as the refrigerant boils.
302 words, about 2 min04Electrical Fundamentals and Controls
Expect Ohm's law, series and parallel circuits, AC versus DC, single- versus three-phase power, and the control devices that sequence a system: thermostats, contactors, relays, transformers, capacitors, pressure switches, limit and safety switches, defrost boards, and lockout controls. You should read a ladder diagram and identify the power circuit versus the control circuit, and know that 24 V control wiring is Class 2 and separate from line voltage.
285 words, about 1 min05Air Distribution, Ductwork, and Indoor Air Quality
Air side questions test static pressure, airflow, duct sizing, and the components that shape airstreams: trunk and branch ducts, takeoffs, dampers, registers, diffusers, and returns. Know that total external static pressure is the sum of supply and return static, that friction rate drives duct sizing (equal-friction method), and that flexible duct must be fully extended with gentle bends to avoid added resistance.
288 words, about 1 min06Heating Systems and Components
Gas furnace knowledge is heavily tested: the sequence of operation from call for heat through inducer, pressure switch proof, ignition, flame proving, and blower delay; the role of the limit switch, rollout switch, flame sensor, and gas valve; and venting categories and combustion air requirements. Understand manifold pressure, gas derating at altitude, and the difference between a standing pilot and a direct-spark or hot-surface ignition system.
299 words, about 1 min07Cooling Systems and Components
Know the compressor families (reciprocating, scroll, rotary, screw, centrifugal), how each handles liquid and pressure ratios, and what failures look like. Understand metering devices: thermostatic and electronic expansion valves, fixed orifices and pistons, capillaries, and automatic expansion valves - and how each responds to load change.
270 words, about 1 min08System Performance, Commissioning, and Diagnostics
This domain ties everything together. You must verify charge using the method the manufacturer specifies - subcooling for TXV systems, target superheat for fixed-orifice systems - and confirm the result with airflow, delta-T, and static pressure.
283 words, about 1 min