EPA 608 Type III Practice Test: 25 Free Questions With Answers

ByJabeer

Quick answer: Type III covers low-pressure appliances: centrifugal and other chillers using R-11, R-123 or R-1233zd that run below atmospheric pressure. The exam is 25 questions, pass mark 18 (72%), proctored. Expect questions on purge units, 25 mm Hg recovery, 10 psig leak-test limits and charging a chiller from a vacuum.

EPA 608 Type III exam at a glance

  • Questions: 25 multiple choice (this practice test: 25)
  • Equipment: low-pressure chillers; refrigerants boil above 50 F at atmospheric pressure
  • Key numbers: recover to 25 mm Hg absolute; leak test at no more than 10 psig; rupture disc 15 psig
  • Pass mark: 18 of 25 correct (72%) on each section
  • Core: must be passed before any Type certification is issued
  • Cost: roughly $25–$150 depending on the program; Type I open-book tests are cheapest
  • Expiry: none — Section 608 certification is for life

How to use this practice test

Click an answer for instant feedback and a short explanation of the rule behind it. Your running score stays pinned at the top; finish all 25 and you will see whether you cleared the 72% line that the real Type III section uses. These are original questions written from EPA’s Section 608 regulations, not copied from any exam, so use them to find weak spots and then read your program’s manual for the exact wording it tests.

Type III — low-pressure

1. Type III certification covers appliances using low-pressure refrigerants, which are defined as refrigerants with a boiling point:

2. Because a low-pressure chiller operates in a vacuum, a leak in the system will cause:

3. The purpose of a purge unit on a low-pressure chiller is to:

4. R-123, the common replacement for R-11 in low-pressure chillers, is in ASHRAE safety group:

5. The ozone depletion potential of R-11 compared with R-123 is:

6. For a low-pressure appliance, recovery equipment manufactured after November 15, 1993 must achieve a vacuum of:

7. When recovering refrigerant from a low-pressure chiller, the technician should remove:

8. During vapour recovery from a low-pressure chiller, condensing the vapour requires:

9. After reaching the required vacuum on a low-pressure chiller, the pressure rises again. This indicates:

10. Why is refrigerant recovered from the chiller’s oil, and how?

11. A rupture disc on a low-pressure chiller is typically set to relieve at:

12. To leak-test a low-pressure chiller, the preferred way to raise its pressure is:

13. The maximum pressure for leak testing a low-pressure chiller is:

14. When charging a low-pressure chiller that is in a deep vacuum, the technician should first add:

15. An excessive purge cycle count on a low-pressure chiller most likely means:

16. Which test detects a leak in a chiller’s water-side tubes into the refrigerant side?

17. A low-pressure chiller containing 1,200 pounds of R-123 serves comfort cooling in an office building. Under Section 608, the owner must repair leaks when the annual leak rate exceeds:

18. If a leak on an appliance subject to the leak-repair rule cannot be repaired within 30 days, the owner may:

19. Records of refrigerant added to a low-pressure chiller must be kept by the owner for:

20. Why is a low-pressure chiller machinery room required to have a refrigerant monitor and ventilation?

21. Before opening a low-pressure chiller for service after recovery, the technician should break the vacuum with:

22. When a low-pressure chiller is opened for a major repair, how should it be dehydrated afterwards?

23. Recovery cylinders used for low-pressure refrigerants should be filled to no more than:

24. A technician holding Type III certification only may NOT service which of the following?

25. How many questions are on the Type III certification exam section, and how many must be answered correctly?

Answer key with explanations

Read straight through as a study sheet, or print it to revise from.

Open the full answer key (25 answers)
  1. 1. B — Above 50 F at atmospheric pressure. Low-pressure refrigerants boil above 50 F at atmospheric pressure, so the evaporator and often the whole machine operate below atmospheric pressure. Examples are R-11, R-123, R-113 and the newer R-1233zd.
  2. 2. B — Air and moisture to be drawn into the system. The system is below atmospheric pressure on the low side, so leaks pull air and moisture in rather than letting refrigerant out. That is why low-pressure chillers are fitted with purge units to remove the non-condensables that collect in the condenser.
  3. 3. D — Remove non-condensable gases (mainly air) that collect in the condenser. Air that leaks in collects at the top of the condenser and raises head pressure. The purge unit separates it from refrigerant vapour and discharges it. Excessive purge run time is a sign of a leak.
  4. 4. B — B1. R-123 is non-flammable but has higher toxicity (B1) with a low occupational exposure limit. Machinery rooms need refrigerant monitors, ventilation and self-contained breathing apparatus available, as required by ASHRAE 15.
  5. 5. C — Much higher. R-11 is a CFC with an ODP of 1.0. R-123 is an HCFC with an ODP of about 0.02. R-1233zd, the current replacement, has essentially zero ODP and very low GWP.
  6. 6. B — 25 mm Hg absolute. Low-pressure appliances must be recovered to 25 mm Hg absolute, which is about 29 inches of mercury vacuum. Equipment made before that date only had to reach 25 inches Hg.
  7. 7. B — Liquid first, then vapour. Liquid is removed first because it moves the bulk of the charge quickly. Vapour recovery follows to reach the required vacuum. Heating the chiller water circuits (not above the maximum) speeds vapour recovery.
  8. 8. A — A compressor and a water-cooled or air-cooled condenser in the recovery unit. Low-pressure recovery units have a compressor to raise the vapour pressure and a condenser to liquefy it into the recovery vessel. A plain vacuum pump would move vapour but could not store it as liquid.
  9. 9. A — Refrigerant is still boiling out of the oil, or a leak is letting air in; wait and recover again. Refrigerant trapped in oil and cold metal continues to vaporise. Repeat recovery until the vacuum holds. A steady rise to atmospheric pressure means air is leaking in.
  10. 10. C — Oil holds a large amount of dissolved refrigerant; it is warmed so the refrigerant boils off and is recovered. Low-pressure refrigerants dissolve readily in oil. Heating the oil (for example with the chiller’s oil heater) releases the refrigerant so it can be recovered before the oil is drained.
  11. 11. D — 15 psig. Low-pressure chillers are built for vacuum and very modest positive pressure. The rupture disc relieves at 15 psig. Pressurising above the rated limit during leak testing will blow the disc and release the charge.
  12. 12. D — Circulating warm water through the tubes or using heating blankets to raise the refrigerant pressure, adding nitrogen if needed, without exceeding 10 psig. Warm water (not above the manufacturer’s limit, usually around 100 F) raises the refrigerant vapour pressure for leak detection. Pressure must never exceed 10 psig, well under the 15 psig rupture disc.
  13. 13. D — 10 psig. Keep leak-test pressure at or below 10 psig. The rupture disc opens at 15 psig, and tubes and seals are not built for high pressure.
  14. 14. D — Vapour refrigerant until the pressure rises above the freezing point of water (about 36 F saturation), then liquid. Liquid refrigerant entering a deep vacuum flashes and can chill the evaporator tubes below 32 F, freezing the water inside and rupturing them. Add vapour first to raise the saturation temperature, then charge liquid.
  15. 15. A — The chiller has a leak admitting air. Purge units only run when non-condensables accumulate. Frequent purging means air is entering through a leak, which should be located and repaired.
  16. 16. C — Checking for water in the refrigerant or oil, and hydrostatic testing of the tube bundle. Tube leaks let water into the refrigerant circuit, where it forms acids and ice. Moisture indicators, oil analysis and pressure or hydrostatic testing of the bundle locate the problem.
  17. 17. B — 10%. Comfort-cooling appliances with 50 lb or more of ODS refrigerant have a 10% threshold. Commercial and industrial process refrigeration have 20%. Repairs are due within 30 days.
  18. 18. B — Develop a retrofit or retirement plan within 30 days and complete it within one year. The rule allows a retrofit or retirement plan as an alternative when repair is not practical. Extensions can apply for industrial process equipment. Records must be kept for three years.
  19. 19. D — 3 years. Owners of appliances with 50 lb or more of ODS refrigerant keep servicing and leak-rate records for three years. Technicians must give the owner an invoice showing the amount of refrigerant added.
  20. 20. D — Because R-123 and similar refrigerants have low exposure limits, are heavier than air and displace oxygen. ASHRAE 15 requires monitoring, alarms and mechanical ventilation for machinery rooms. A self-contained breathing apparatus should be available for emergencies.
  21. 21. D — Dry nitrogen. Breaking the vacuum with dry nitrogen keeps moisture out of the machine while it is open. Air would bring humidity into a system that must later be dehydrated.
  22. 22. A — Evacuate with a vacuum pump, using a micron gauge, until the vacuum holds. Deep evacuation boils off moisture. A micron gauge confirms the system is dry and tight when the vacuum stops rising after the pump is isolated.
  23. 23. B — 80%. The 80% rule applies to every refrigerant. Low-pressure refrigerants are dense liquids, so weigh the cylinder and respect its water capacity rating.
  24. 24. C — A 40-ton R-410A rooftop unit. Type III is limited to low-pressure appliances. A high-pressure R-410A rooftop unit needs Type II or Universal certification.
  25. 25. C — 25 questions, 18 correct. Every Section 608 exam section has 25 questions and a pass mark of 18 (72%). The Core section must also be passed before any Type certification is awarded.

Questions people ask about the EPA 608 Type III exam

How many questions are on the EPA 608 Type III exam?

25 multiple-choice questions, like every Section 608 section. You need 18 correct (72%). Most programs give one combined sitting of Core plus whichever Types you register for.

Is the EPA 608 Type III test open book?

Only Type I may be offered as a non-proctored open-book test by mail or online. Core, Type II and Type III must be proctored, either in person or by an online proctor.

Does EPA 608 certification expire?

No. Section 608 certification is valid for life. If you lose your card, see our EPA 608 certification lookup guide for how to get a replacement.

Do I need Type III if I never work on chillers?

No. Type III is only needed for low-pressure appliances. Most technicians take it anyway to earn Universal certification, since the extra section is cheap at the same sitting.

Related guides

Sources

Related problems

See all EPA 608 Certification guides →

Leave a Reply

Your email address will not be published. Required fields are marked *