This practice test is designed to help candidates prepare for the Appliance Repair Technician (NASTeC) Certification.
It covers topics commonly found on the exam, including appliance components, troubleshooting procedures, electrical and gas principles, and safety standards.
Each question is multiple-choice with one correct answer.
Review the questions carefully and check your answers at the end.
Good Luck!
Appliance Repair Technician (NASTeC) Certification Practice Test
Congratulations - you have completed Appliance Repair Technician (NASTeC) Certification Practice Test.
You scored %%SCORE%% out of %%TOTAL%%.
Your performance has been rated as %%RATING%%
Your answers are highlighted below.
Question 1 |
What is the typical resistance reading for a good dryer heating element?
10–15 ohms | |
100–150 ohms | |
0.5–2 ohms | |
30–40 ohms |
Question 2 |
What color wire typically indicates ground in a 120V household circuit?
Red | |
Green | |
Black | |
Blue |
Question 3 |
A refrigerator evaporator fan motor is not running. Which tool is best for diagnosing this issue?
Clamp meter | |
Non-contact voltage tester | |
Multimeter | |
Circuit tracer |
Question 4 |
What is the purpose of a thermistor in modern appliances?
Acts as a fuse | |
Regulates motor speed | |
Measures temperature | |
Powers heating coils |
Question 5 |
What is the function of the start relay on a refrigerator compressor?
Lowers voltage to compressor | |
Discharges the capacitor | |
Helps the compressor start | |
Prevents overheating |
Question 6 |
On a gas dryer, what component ignites the burner?
Flame sensor | |
Igniter | |
Thermostat | |
High-limit switch |
Question 7 |
What voltage would you expect across a properly functioning heating element on a 240V dryer?
240V | |
120V | |
0V | |
60V |
Question 8 |
A clogged dryer vent most directly causes:
Electrical shorts | |
Overheating | |
Poor ignition | |
Rust formation |
Question 9 |
What is the correct tool to use when checking for a gas leak?
Thermal camera | |
Flame lighter | |
Electronic leak detector | |
Ohmmeter |
Question 10 |
In appliance repair, what does the acronym GFCI stand for?
Ground Fault Circuit Interrupter | |
Gas Flow Control Interface | |
Grounding Fuse Circuit Indicator | |
General Fuse Circuit Indicator |
Question 11 |
Which certification is required when working on a sealed refrigeration system?
NASTeC Basic | |
EPA Section 608 | |
OSHA 10 | |
ANSI 107 |
Question 12 |
What does a continuity test determine?
Gas pressure | |
Voltage | |
Open or closed electrical path | |
Circuit amperage |
Question 13 |
What is the purpose of a capacitor in a washer motor?
Increase resistance | |
Start the motor | |
Lower frequency | |
Transfer torque |
Question 14 |
Which of the following uses a thermocouple for safety?
Electric oven | |
Gas oven | |
Refrigerator | |
Microwave |
Question 15 |
What happens if a refrigerator door gasket is torn?
The compressor stops running | |
Cooling improves | |
Warm air enters | |
Water leaks increase |
Question 16 |
What is the most common cause of a front-load washer not draining?
Faulty inlet valve | |
Drain pump obstruction | |
Broken belt | |
Control board failure |
Question 17 |
What component detects the temperature inside a modern oven?
Thermostat | |
Thermal fuse | |
Thermistor | |
Bimetal sensor |
Question 18 |
What tool would you use to measure current flow?
Thermometer | |
Megohmmeter | |
Clamp meter | |
Voltmeter |
Question 19 |
What does a “no heat” condition in an electric dryer typically indicate?
Blown thermal fuse | |
Door latch issue | |
Ventilation restriction | |
Defrost timer fault |
Question 20 |
When checking a defrost heater, which set should your multimeter be on?
Voltage AC | |
Resistance (Ohms) | |
Amps DC | |
Continuity |
Question 21 |
In microwave ovens, what component generates microwaves?
Solenoid | |
Magnetron | |
Diode | |
Inverter |
Question 22 |
What happens when a dishwasher float switch is stuck up?
Dishwasher won't fill | |
Water overheats | |
Drain motor shuts off | |
Spray arms spin faster |
Question 23 |
Which of these indicates a proper compressor start-up?
Silent motor | |
Vibration and hum | |
Click then off | |
Sparking noise |
Question 24 |
If a gas oven has a glowing igniter but no flame, what is the likely fault?
Weak igniter | |
Faulty thermostat | |
Broken control board | |
Gas valve stuck open |
Question 25 |
What component prevents a washer from spinning with the lid open?
Motor coupler | |
Door lock | |
Lid switch | |
Agitator |
Question 26 |
What is the recommended torque for a sealed system access valve?
10 in-lbs | |
15 ft-lbs | |
20 in-lbs | |
5 ft-lbs |
Question 27 |
In an electric range, what component regulates surface element temperature?
Surface switch | |
Circuit board | |
Relay | |
Infinite switch |
Question 28 |
What gas is commonly used in household refrigeration systems today?
R-22 | |
R-410A | |
R-134a | |
Ammonia |
Question 29 |
Which color wire is typically hot in a 240V dryer?
Green | |
White | |
Black | |
Red |
Question 30 |
What happens when a thermal fuse blows in a dryer?
Motor speeds up | |
Dryer will not start | |
Dryer spins but doesn’t heat | |
Heat cycles more frequently |
Question 31 |
In a front-load washer, the door lock is primarily a:
Temperature sensor | |
Safety interlock | |
Speed controller | |
Water seal |
Question 32 |
What tool is ideal for checking air temperature in a freezer?
Laser level | |
Infrared thermometer | |
Clamp meter | |
Spirit level |
Question 33 |
What happens if a gas oven safety valve doesn’t receive sufficient current?
Igniter glows brighter | |
Valve stays closed | |
The burner overheats | |
Flame sensor fails |
Question 34 |
What is the purpose of an inverter board in modern refrigerators?
Switch voltage polarity | |
Adjust compressor speed | |
Control lights | |
Heat water |
Question 35 |
Which component would you test for continuity in a dryer that's overheating?
Drive motor | |
Drum belt | |
Cycling thermostat | |
Drum roller |
Question 36 |
What must be done before testing a capacitor?
Freeze it | |
Tap it | |
Discharge it | |
Ground it |
Question 37 |
A washer doesn’t spin. The belt is intact. What should you check next?
Water inlet valve | |
Lid switch | |
Agitator | |
Detergent level |
Question 38 |
What part circulates air inside a convection oven?
Igniter | |
Convection fan | |
Blower motor | |
Cooling coil |
Question 39 |
What does a PTC relay do?
Open at high temperatures | |
Shorten ignition | |
Start the compressor then open | |
Fuse current |
Question 40 |
What causes a refrigerator to run constantly?
Door left open | |
Thermistor failure | |
Low refrigerant | |
All of the above |
Question 41 |
What must always be worn when brazing?
Latex gloves | |
Welding goggles | |
Steel-toe boots | |
Rubber apron |
Question 42 |
What tool is used to recover refrigerant from an appliance?
Vacuum pump | |
Recovery machine | |
Air compressor | |
Expansion valve |
Question 43 |
What is the purpose of a defrost timer?
Prevent fan damage | |
Switch to cooling mode | |
Cycle between cooling and defrosting | |
Reset compressor |
Question 44 |
Which of these tools can detect open windings in motors?
Micrometer | |
Inductive tester | |
Ohmmeter | |
Torque wrench |
Question 45 |
What is the first thing to check if a microwave isn’t turning on?
Door switch | |
Magnetron | |
Turntable motor | |
Diode |
Question 46 |
Why is a sealed system considered closed-loop?
Contains fuses | |
It’s ungrounded | |
Refrigerant circulates without exposure | |
Uses high-voltage |
Question 47 |
What controls burner cycles in a gas dryer?
Moisture sensor | |
Gas valve coil | |
Cycling thermostat | |
Drum switch |
Question 48 |
What causes a humming noise from a stuck motor?
Low voltage | |
Open fuse | |
Locked rotor | |
Cooling fan |
Question 49 |
What component reduces voltage spikes in a microwave?
Rectifier | |
Capacitor | |
Varistor | |
Transformer |
Question 50 |
What steps should always be taken before servicing an appliance?
Vacuum it | |
Run diagnostics | |
Disconnect power | |
Clean filters |
Once you are finished, click the button below. Any items you have not completed will be marked incorrect.
There are 50 questions to complete.
Featured Online Programs
Learn at home, at your own pace.
Sponsored Online Programs
Featured Online Programs
Learn at home, at your own pace.
Sponsored Online Programs






