HVAC Electrical Practice Test

Electricity runs through every NATE exam. These questions cover the theory: the Core exam tests it under Using Basic Science and the Support Technician exam under Introduction to Basic Electricity.

Take the timed NATE Core mock exam

50 questions on the 90-minute clock, weighted like NATE’s Core outline, with a score for every area and an explanation for every option.

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  • 30 original electrical questions, every option explained
  • Tested on: NATE Core, NATE HVAC Support Technician
Free sample · Question 1 of 3Electrical

A typical US home has single-phase split service. Which voltages are available?

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What our electrical questions cover

  • Basic terms: volts, amps, ohms and watts, conductors and insulators, open and short circuits
  • Ohm’s law and power calculations
  • Series and parallel circuits: resistance, current and voltage
  • AC and DC, 60 hertz, polarity, magnetism and electromagnets
  • Transformers: control transformers, turns ratio and VA rating; residential 120/240-volt service
  • Loads and solid state: inductive and resistive loads, power factor, capacitors, diodes, thermistors
Line drawing of a control transformer with wire leads, a relay, a coil of copper wire, an electromagnet and a multimeter

This list is our own summary, written for practice. NATE publishes the full topic lists in its Knowledge Areas of Technician Expertise (KATEs).

Drill electrical, then sit the full NATE Core exam

Take the timed NATE Core mock exam

50 questions on the 90-minute clock, weighted like NATE’s Core outline, with a score for every area and an explanation for every option.

Or try the free electrical drill

Ideas the questions test most

  1. E = I × R and P = E × I.
  2. Series: same current, voltages add. Parallel: same voltage, currents add.
  3. Two equal resistors in parallel give half the resistance of one.
  4. Control transformers step line voltage down to 24 VAC; current capacity = VA ÷ volts.
  5. Low voltage makes a loaded motor draw more current and run hotter.

Start the free electrical drill · NATE Core practice test · NATE HVAC Support Technician practice test

Common questions

How much electrical is on the NATE Core exam?

Basic Electricity is the largest Core domain at 26%, covering diagrams, motors and meters. Electrical theory (circuits, Ohm’s law, magnetism, transformers) sits in Using Basic Science, another 10%. Our wiring diagrams and motors topic covers the first; this topic covers the second.

Is Ohm’s law on the NATE exams?

Yes. The Core KATE lists Ohm’s law in DC circuits, series and parallel circuits and current distribution in multiple-load circuits.

Take the timed NATE Core mock exam

50 questions on the 90-minute clock, weighted like NATE’s Core outline, with a score for every area and an explanation for every option.

Or try the free electrical drill

More HVAC topics

Exam format and outline checked November 2026 on natex.org: NATE: Ready-to-Work and HVAC Support Technician certificates · NATE Ready-to-Work KATE (PDF) · NATE HVAC Support Technician KATE (PDF) · NATE Core Exam KATE (PDF) · NATE: Frequently asked questions. NATE has not announced a change to this outline.

NATE is a mark of North American Technician Excellence, Inc. Game Assessment Prep is an independent practice site, not affiliated with or endorsed by NATE. Every question is original; none is taken from NATE exams, NATE study guides or another prep provider.