EPA Section 608 — Core
Recovery, recycling and reclamation: practice questions
Our EPA 608 Core bank has 7 questions on this topic. Here are 5 of them with answers; the full mock exam draws from every topic, like the real one.
Question 1
Which instrument accurately measures a deep vacuum during dehydration?
- A compound gauge
- A micron gauge
- A thermometer
- An ammeter
Show the answer
B. A micron gauge — Compound gauges are not accurate enough for deep vacuum.
Question 2
How can the speed of recovery be increased?
- By chilling the recovery cylinder and recovering liquid first
- By using longer, narrower hoses
- By opening the appliance to air
- By heating the recovery cylinder with a torch so the refrigerant moves faster
Show the answer
A. By chilling the recovery cylinder and recovering liquid first — Lowering the cylinder pressure speeds transfer; short, large-diameter hoses help.
Question 3
What should be checked on recovery equipment before use?
- The oil level, filter-drier and hoses for leaks
- The brand of refrigerant in the system and the colour of the cylinder
- Nothing
- The colour of the paint
Show the answer
A. The oil level, filter-drier and hoses for leaks — Change filters and oil as recommended to avoid cross-contamination.
Question 4
Why should a system be evacuated with a vacuum pump before charging?
- To raise the pressure
- To test the compressor's electrical circuit before refrigerant is added
- To add oil
- To remove air and moisture (non-condensables)
Show the answer
D. To remove air and moisture (non-condensables) — Moisture forms acids and sludge; air raises head pressure.
Question 5
Why must recovery equipment be evacuated before recovering a different refrigerant?
- To prevent mixing refrigerants
- To check the voltage
- To cool the compressor before the next job
- To add oil
Show the answer
A. To prevent mixing refrigerants — Some machines have to be purged according to the manufacturer's instructions.