HVAC Practice Test
Free HVAC questions across electrical, the refrigeration cycle, airflow, heating and controls — every answer explained, with a direct path into free interactive diagnostic labs.
- Interactive decision labs
- Built by working technicians
- Path-based verifiable certificate
- Exam preparation only
- Worldwide online
General HVAC practice questions
Mixed practice across electrical, the refrigeration cycle, airflow, heating and safety, with an explanation on every answer. Use it to find your weak area, then work the matching diagnostic lab.
A contactor coil is rated 24 V but measures 0 Ω across the coil terminals. This means:
Preparing for a specific exam?
Refrigerant handling is examined separately from general HVAC knowledge. If you are working towards refrigerant certification, start with the EPA 608 practice questions and the certification prep hub, then come back here for the wider fundamentals.
Free diagnostic labs by fault
Questions test recall. These graded decision labs test whether you can work the call: one decision at a time, readings that fill in as you check, coaching when you take a wrong turn. Free, no login.
Residential no-cool
Verify the call, work the electrical chain, confirm the fault and prove the repair.
Walk-in cooler not holding temperature
Commercial refrigeration diagnosis with real readings and coaching on wrong turns.
Ice machine not making ice
Water, harvest control and condenser checks on a machine that runs but produces nothing.
RTU gas heat no-heat
Follow the ignition sequence: inducer, pressure switch, ignitor drive, flame sense.
Questions technicians ask
- Who is this HVAC practice test for?
- Apprentices, trade-school students, technicians preparing for a certification exam, and anyone sitting a pre-employment HVAC knowledge test.
- Does this issue a certification?
- No. It is free study material. Official credentials are issued by the relevant certifying bodies — EPA-approved organizations, NATE, SAQCC, EPRA, ESSCI and others in your region.
- What topics are covered?
- Electrical, the refrigeration cycle, airflow and static pressure, heat pumps, heating, refrigerant handling, controls and commercial equipment basics.
- What is a diagnostic lab?
- An interactive, graded decision simulation. You get a complaint, a unit and site notes, then choose each next check. Readings fill in as you work, wrong turns are coached, and the debrief shows how a senior technician would have worked the call.