EPA 608 Type III practice test

Answer: B. Controlled hot water, or a built-in system heating/pressurization device such as Prevac

EPA's Type 3 leak-detection topics give the order of preference for pressurizing a low-pressure system: first the hot water method or a built-in heating/pressurization device such as Prevac, then nitrogen. EPA's Core safety topics say to use nitrogen rather than oxygen or compressed air for leak detection, which rules out choices A and C. Choice D is not on EPA's low-pressure list. The CFR takes a similar heat-first approach when a low-pressure appliance is pressurized for a non-major repair: for refrigerants that boil above 85 °F at 29.9 inches of mercury, 40 CFR 82.156(a)(1)(ii) requires heat to be used as much as possible before nitrogen, and for refrigerants that boil at or below 85 °F it bars methods such as nitrogen that require later purging.

Source: EPA Section 608 Test Topics, Type 3 (Low-pressure), https://www.epa.gov/section608/test-topics (accessed 2026-10-21); EPA Section 608 Test Topics, Core (Safety), same URL; 40 CFR 82.156(a)(1)(ii), eCFR as of 2026-10-19 (accessed 2026-10-21)

Answer: A. Once per calendar year, until leak rate calculations show the chiller has not leaked above the applicable rate for one year

R-123 (HCFC-123) is a class II ozone-depleting substance, so this 600-lb chiller is covered by 40 CFR 82.157. Section 82.157(g)(1)(iii) requires leak inspections once per calendar year for comfort-cooling appliances and other appliances not covered by (g)(1)(i)-(ii), until the owner can show through leak rate calculations that the appliance has not leaked above the applicable rate for one year. Choice B is the schedule in (g)(1)(i), which applies only to commercial refrigeration and industrial process refrigeration appliances with a full charge of 500 or more pounds, so a 600-lb comfort chiller does not move to quarterly. Inspections are skipped only where an automatic leak detection system that is audited or calibrated annually is in place (82.157(g)(4)), and this chiller has none.

Source: 40 CFR 82.157(g)(1) and (g)(4), eCFR as of 2026-10-19 (accessed 2026-10-21); EPA, Ozone-Depleting Substances, https://www.epa.gov/ozone-layer-protection/ozone-depleting-substances (accessed 2026-10-21)

Answer: A. 10 percent

40 CFR 82.152 defines comfort cooling as air-conditioning appliances that control heat and/or humidity in occupied facilities such as office buildings, and names chillers as an example. EPA's leak repair page also lists chillers under comfort cooling. 82.157(c)(2)(iii) sets a 10 percent leak rate for comfort-cooling appliances. 20 percent applies to commercial refrigeration and 30 percent to industrial process refrigeration. 35 percent is from the old 82.156(i).

Exam note: Before January 1, 2019, the old 82.156(i) used a 15 percent rate for comfort cooling and 35 percent for commercial and industrial process refrigeration. Older study materials may still list those figures. The current rates are 10, 20 and 30 percent.

Source: 40 CFR 82.152 "Comfort cooling"; 40 CFR 82.157(c)(2), eCFR as of 2026-10-19 (accessed 2026-10-21); EPA, Stationary Refrigeration Leak Repair Requirements, https://www.epa.gov/section608/stationary-refrigeration-leak-repair-requirements (accessed 2026-10-21)

Answer: B. 40 CFR 84.106 (AIM Act leak repair), which applies to appliances with 15 or more pounds of a regulated HFC

Since April 10, 2020, 40 CFR 82.157(a) applies only to appliances with 50 or more pounds of a class I or class II refrigerant (or a blend containing one), and not to appliances containing only substitute refrigerants. R-245fa is an HFC, so 82.157 does not apply. 40 CFR 84.106(a) covers appliances with a full charge of 15 or more pounds where the refrigerant contains a regulated substance, starting January 1, 2026. HFC-245fa is listed in Appendix A to part 84 as a regulated substance. Under 84.106(c)(2)(iii), the leak rate for comfort cooling is 10 percent.

Exam note: Banks written from 2017 to 2019 teach that 82.157 covers HFCs at 50 or more pounds (2016 rule). EPA rescinded that for substitutes effective April 10, 2020. HFC leak repair now sits in 40 CFR 84.106 (15 lb, from January 1, 2026). Re-check the Federal Register for amendments to 84.106 before each release.

Source: 40 CFR 82.157(a), eCFR as of 2026-10-19 (accessed 2026-10-21); 40 CFR 84.106(a) and (c)(2), eCFR as of 2026-10-19 (accessed 2026-10-21); 40 CFR part 84, Appendix A, eCFR as of 2026-10-19 (accessed 2026-10-21)

Answer: D. 130 °F

EPA's Type 3 recovery-technique topics list the "need to heat oil to 130°F before removing it to minimize refrigerant release." EPA's service practice page explains that oil can contain large amounts of dissolved refrigerant. 85 °F is the boiling-point cutoff in the nitrogen rule of 40 CFR 82.156(a)(1)(ii), and 104 °F is the reference temperature in the low-pressure appliance definition (82.152). Neither is an oil-heating temperature.

Source: EPA Section 608 Test Topics, Type 3 (Low-pressure), https://www.epa.gov/section608/test-topics (accessed 2026-10-21); EPA, Stationary Refrigeration Service Practice Requirements, https://www.epa.gov/section608/stationary-refrigeration-service-practice-requirements (accessed 2026-10-21)

Answer: A. Vapor, to prevent freezing of the water in the tubes

EPA's Type 3 recharging topics list the "need to introduce vapor before liquid to prevent freezing of water in the tubes." Liquid admitted into a deep vacuum boils at a very low temperature, because boiling temperature falls as pressure falls (Refrigeration 101). Charging vapor first raises the pressure before liquid is added. Choice D is wrong because nitrogen is not a refrigerant charge.

Source: EPA Section 608 Test Topics, Type 3 (Low-pressure), https://www.epa.gov/section608/test-topics (accessed 2026-10-21); EPA-hosted GreenChill webinar slides, Refrigeration 101, https://www.epa.gov/sites/default/files/documents/Refrigeration_101.pdf (accessed 2026-10-21)

Answer: B. Pressurized to a pressure no higher than 0 psig before it is opened

40 CFR 82.156(a)(1) applies when evacuation of the appliance to the atmosphere is not to be performed after the work and the work is not major. Under (a)(1)(ii), a low-pressure appliance must be pressurized to a pressure no higher than 0 psig before it is opened, and openings must be covered when isolation is not possible. Medium-, high- and very high-pressure appliances are instead evacuated to no higher than 0 psig (a)(1)(i). Covering openings is an added requirement, not a substitute for the pressure limit, so choice A is wrong.

Source: 40 CFR 82.156(a)(1), eCFR as of 2026-10-19 (accessed 2026-10-21); EPA, Stationary Refrigeration Service Practice Requirements, https://www.epa.gov/section608/stationary-refrigeration-service-practice-requirements (accessed 2026-10-21)

Answer: A. Removing the condenser

40 CFR 82.152 defines major maintenance, service, or repair as work that removes the compressor, condenser, evaporator, or auxiliary heat exchange coil, or that uncovers an opening of more than four square inches of flow area for more than 15 minutes. Choice B is under the area limit, and choice C is under the time limit. Both conditions must be exceeded for an opening to count. Replacing a fuse does not remove any of the listed components.

Source: 40 CFR 82.152 "Major maintenance, service, or repair", eCFR as of 2026-10-19 (accessed 2026-10-21)

Answer: C. 5 psig

40 CFR 82.156(a)(1)(iii) says that for oil changes the appliance must be evacuated or pressurized to a pressure no higher than 5 psig before it is opened. The alternative is to drain the oil into a system receiver that is then evacuated or pressurized to no higher than 5 psig. EPA's service practice page adds that it is a violation to change oil at higher than 5 psig, because oil can hold large amounts of dissolved refrigerant. 0 psig is the limit for non-major repairs in (a)(1)(i)-(ii), not for oil changes.

Source: 40 CFR 82.156(a)(1)(iii), eCFR as of 2026-10-19 (accessed 2026-10-21); EPA, Stationary Refrigeration Service Practice Requirements, https://www.epa.gov/section608/stationary-refrigeration-service-practice-requirements (accessed 2026-10-21)

Answer: D. Below atmospheric pressure (a vacuum)

Boiling temperature follows pressure: as pressure decreases, boiling temperature decreases (Refrigeration 101). This refrigerant boils above 85 °F at standard atmospheric pressure. At 70 °F, below that boiling point, its saturation pressure must be lower than atmospheric, so the chiller is in a vacuum. That is why 40 CFR 82.156(a)(1)(ii) requires heat to raise the internal pressure of such appliances before they are opened. 45 psia at 104 °F is the upper limit in the 82.152 low-pressure appliance definition, not the pressure at 70 °F.

Source: EPA-hosted GreenChill webinar slides, Refrigeration 101, https://www.epa.gov/sites/default/files/documents/Refrigeration_101.pdf (accessed 2026-10-21); 40 CFR 82.152 "Low-pressure appliance" and 82.156(a)(1)(ii), eCFR as of 2026-10-19 (accessed 2026-10-21)