EPA 608 Type II · Safety · Hard
Why must you never start a hermetic compressor while it is in a deep vacuum?
Answer: B. The electrical motor windings will arc and burn out.
- AThe compressor will pump oil into the condenser.
- BThe electrical motor windings will arc and burn out.✓ Correct
- CThe internal valves will shatter.
- DThe crankcase heater will explode.
Why B is right
In a vacuum, the dielectric strength is gone; applying power causes the motor windings to short/arc.
More Type II questions
- What service pressure rating must a recovery cylinder have to hold R-410A?
- Recovering R-454B, an A2L refrigerant, requires what kind of recovery machine?
- Why must you never pressurize a refrigeration system with oxygen or compressed air?
- Can you pipe two pressure relief valves in series?
- R-22 has a saturation pressure of about 220 psia at 104°F. Which EPA category does an R-22 appliance fall in?
Go deeper with the study guide A2L Refrigerants and the R-410A Transition: A Tech’s Guide, try the free 10-question test or browse all EPA 608 practice questions.
A practice question written for study, checked against 40 CFR Part 82, Subpart F. It is not an official EPA exam question, and this site is not affiliated with the U.S. EPA.