EPA 608 Type II Study Guide: Leak Checks, Recovery and Evacuation for High-Pressure Systems

What the EPA 608 Type II section covers

Type II is the 25-question section for medium-, high- and very high-pressure appliances, except small appliances and motor vehicle air conditioning (40 CFR 82.161(a)(1)(ii)). EPA's Test Topics page labels it "Type 2 (High-Pressure)," and EPA's certification requirements page mentions only high- and very high-pressure appliances, but the regulation covers medium-, high- and very high-pressure equipment alike, and this guide follows the regulation. That takes in residential split systems and heat pumps, ductless mini-splits, packaged rooftop units, walk-ins and supermarket racks. Off-road vehicle air conditioning (MVAC-like appliances) can be serviced with Type II or Section 609 certification.

EPA's Test Topics page groups Type II under six headings: leak detection, leak repair requirements, recovery techniques, recovery requirements, refrigeration, and safety. The sections below follow that order, with the reasoning each question rewards.

Leak detection on high-pressure systems

EPA's topics name three things to know:

• Signs of a leak. "Excessive superheat" and "traces of oil for hermetics." Fluke Corporation's application note on superheat and subcooling explains the first: high superheat means the evaporator is being starved of refrigerant, and an undercharged system is one cause. Fluke also lists other causes, such as a restriction, a blocked filter-drier or a faulty metering device, so superheat points you toward a leak search rather than proving one
• Leak test before charging. Test before you charge or recharge equipment, not after
• Which gas to use. EPA's order of preference: nitrogen alone is best, nitrogen with a trace of HCFC-22 is next, and pure refrigerant is least preferred

The regulation also separates finding that a system leaks from finding where. Under 40 CFR 82.152, a leak inspection must locate leaks, using methods such as ultrasonic tests, gas-imaging cameras, bubble tests or a properly maintained leak detector. Standing pressure or vacuum decay tests, sight glass checks, receiver levels, pressure checks and charging charts only show that a system is leaking, so they must be paired with a method that finds the leak.

Leak repair for appliances with 50 pounds or more of ozone-depleting refrigerant

Since April 10, 2020, the Part 82 leak repair rules in 40 CFR 82.157 apply only to appliances with a full charge of 50 pounds or more of a class I or class II refrigerant, such as R-22, or a blend containing one. The trigger depends on what the appliance is used for, as defined in 40 CFR 82.152:

What follows a leak above the trigger (40 CFR 82.157):

• Repair within 30 days of the refrigerant addition that showed the excess, or 120 days if an industrial process shutdown is needed, with the leaks located by a certified technician
• Verification tests. An initial verification test before refrigerant is added back, and a follow-up verification test within 10 days of the successful initial test, or within 10 days of the appliance reaching normal operating conditions if it was evacuated for the repair. EPA's technician questions-and-answers page still says 30 days; the regulation's 10 days is the rule that applies
• Extensions. If parts are not available in time, up to 30 days after they arrive, capped at 180 days (270 with an industrial process shutdown) from the date the trigger was exceeded. The owner must request the extension from EPA within the repair period
• Follow-up leak inspections. Every three months for commercial and industrial process refrigeration with 500 pounds or more, and once a year for smaller ones and for comfort cooling, until the leak rate stays under the trigger. A continuously monitoring automatic leak detection system audited or calibrated each year can replace them
• Chronic leakers. An appliance that leaks 125% or more of its full charge in a calendar year must be reported to EPA by March 1 of the next year
• Your paperwork. Anyone who adds or removes refrigerant must give the owner or operator documentation of the service (82.157(b))

Two traps from older study material. First, the 35% and 15% triggers some guides still print are the pre-2019 rule: EPA's regulatory updates page says the 2016 rule lowered them to 30% for industrial process refrigeration, 20% for commercial refrigeration and 10% for comfort cooling. Second, HFC appliances now have their own leak repair rule, 40 CFR 84.106, for 15 pounds or more of an HFC or a substitute with a GWP above 53, in force since January 1, 2026 and excluding residential and light commercial air conditioning and heat pumps. EPA's Test Topics still frame leak rates in Part 82 terms, so learn those for the test; the EPA refrigerant rules for 2027 guide covers Part 84 on the job.

A worked EPA 608 leak rate calculation

40 CFR 82.152 allows two methods, and a facility must use the same one for all its appliances. Here is the annualizing method on a fictional example: an air-cooled R-22 chiller cooling an office building (comfort cooling) has a full charge of 120 pounds. A technician adds 6 pounds, 146 days after the last addition.

12.5% is above the 10% comfort cooling trigger, so the leaks must be found and repaired within 30 days. The same 6 pounds added after a full year would have been 5%, under the trigger, which is why the time since the last addition matters. The other method, the rolling average, sums the pounds added over the previous 365 days (or since the last successful follow-up verification test, if that is less than a year), divides by the full charge and multiplies by 100. Leak-rate triggers are among the numbers the Part 82 leak-rate flashcards planned for EPA 608 at launch drill by appliance type.

Speeding up recovery and keeping refrigerant clean

EPA's Type II recovery techniques:

1. Recover liquid first. Removing liquid at the start of recovery speeds the process.
2. Use temperature. Chilling the recovery vessel, or heating the appliance or vessel you are recovering from, speeds recovery further.
3. Avoid cross-contamination. Know the methods for reducing cross-contamination and emissions when a recovery or recycling machine is used with a new refrigerant. The regulation adds that equipment must be used according to the manufacturer's directions (40 CFR 82.156(g)).
4. Wait before you open. After reaching the required vacuum, wait a few minutes to see whether the pressure rises. A rise means refrigerant is still in the system, as liquid or dissolved in the oil.

Evacuation requirements on the EPA 608 Type II test

Before opening or disposing of a Type II appliance, you evacuate it to the Table 1 level for its pressure class, charge size and recovery-equipment date, and verify that level before opening (40 CFR 82.156(a)). The full table is in the EPA 608 numbers guide. Questions here usually hide one condition in the scenario, and in planned EPA 608 prep each explanation names the Part 82 rule that decides it. The conditions that change the answer:

• Major or not. A repair is "major" if it removes the compressor, condenser, evaporator or auxiliary heat exchange coil, or uncovers an opening of more than 4 square inches of flow area for more than 15 minutes (40 CFR 82.152). For a repair that is not major and is not followed by evacuation to the atmosphere, 0 psig before opening is enough
• Leaky or not. If leaks make Table 1 levels impossible, isolate leaking from non-leaking parts, take non-leaking parts to Table 1, and take leaking parts as low as you can without substantially contaminating the refrigerant, never above 0 psig
• Charge size. The 200-pound line splits the high- and medium-pressure rows
• Equipment date. Recovery equipment made before or after November 15, 1993
• System-dependent limit. Passive recovery equipment cannot be used on appliances with more than 15 pounds of refrigerant unless it is a permanently attached pump-out unit (40 CFR 82.156(e))

Reading a pressure-temperature chart for EPA 608 Type II

EPA's refrigeration topics ask you to know how to identify the refrigerant in an appliance and the pressure-temperature relationships of common high-pressure refrigerants, using a standard chart and remembering to add 14.7 to turn psig into psia. ESCO Institute allows its 2026 chart during its exam, and that chart groups refrigerants by their gauge pressure at 104 °F, the temperature in EPA's pressure-class definitions:

Two readings from the same chart, worked both ways:

• R-410A at 104 °F: 336 psig. Add 14.7 and you get 350.7 psia, inside EPA's 170 to 355 psia high-pressure band
• R-22 at 104 °F: 208 psig, or 222.7 psia, also high pressure

EPA also lists the components of high-pressure appliances (the topic names the receiver, evaporator and accumulator) and the state of the refrigerant in each. Fluke's note gives the basic loop: hot gas leaves the compressor, condenses to liquid in the condenser, drops in pressure at the metering device, and boils back to vapor in the evaporator. Place each named component on the high or low side of that loop and you can work out whether it normally holds liquid or vapor. One more refrigeration item: EPA lists "the idea that hydrocarbons are not approved for retrofits."

Type II safety and the equipment room

• Never energize a hermetic compressor under vacuum, a Type II safety topic
• Equipment rooms. EPA's topic cites ASHRAE Standard 15 equipment room requirements, worded on the Test Topics page as an "oxygen deprivation sensor with all refrigerants"
• Pressure testing. Use nitrogen through a regulator with a relief valve, as the EPA 608 Core study guide explains

Two Passy practice questions for EPA 608 Type II

These are original Passy questions, not EPA items.

1. A supermarket rack (commercial refrigeration) has a full charge of 400 pounds of R-22. A technician adds 20 pounds, 73 days after the last addition. Using the annualizing method, what is the leak rate, and what follows?

• A. 25%, above the 20% commercial refrigeration trigger, so repairs are required
• B. 5%, below every Part 82 trigger, so the owner takes no further action
• C. 25%, below the 30% trigger for this system, so no repair is required
• D. 20%, exactly at the trigger, so repair is optional for the owner here

Answer: A. 20 ÷ 400 = 0.05, 73 ÷ 365 = 0.2, and 0.05 ÷ 0.2 = 0.25, or 25%. Commercial refrigeration triggers at 20%, so repairs are due within 30 days. The 30% trigger in C belongs to industrial process refrigeration, and B skips the annualizing step.

2. Which step speeds up recovery from a large split system?

• A. Recover the liquid first, then the remaining vapor
• B. Use the longest and narrowest hoses on the truck
• C. Warm the recovery cylinder before starting recovery
• D. Recover the vapor first so the liquid stays in place

Answer: A. EPA's topics say recovering liquid at the start speeds the process. Hose length and diameter affect recovery speed, so long, narrow hoses slow it (B), and EPA lists chilling the recovery vessel, not warming it, as a way to speed recovery (C).

Studying Type II after the Core

Type II is heavy on regulation, so give it time after Core: first the leak-rate table and the calculation, then evacuation conditions, then the chart. The free EPA 608 practice questions include five Type II items with explanations, and the EPA 608 study plan can give Type II extra days. Full prep at launch plans 194 Type II questions for EPA 608, practiced alone or mixed. If you also work on chillers, the EPA 608 Type III study guide is the natural next section.