What EPA 608 Type 2 certification covers, and what Type 2 means on the exam form
EPA 608 Type 2 certification covers technicians who maintain, service, repair, or dispose of medium pressure, high pressure, and very high pressure appliances, except small appliances and MVAC, under 40 CFR 82.161. 40 CFR 82.152 classifies an appliance by the liquid phase saturation pressure of its refrigerant at 104°F: medium pressure is 45 to 170 psia (R-12, R-134a, R-500), high pressure is 170 to 355 psia (R-22, R-407C, R-410A, R-502), and very high pressure is above 355 psia or a critical temperature below 104°F (R-13, R-23, R-503).
Equipment covered under Type 2 includes residential split systems and heat pumps, commercial split systems, packaged rooftop units, walk in coolers and freezers, commercial refrigeration cases, reach in refrigeration units, and any other equipment that operates at positive gauge pressure.
A high pressure system moves refrigerant through six components, and the exam tests the pressure and state of the refrigerant at each one:
| Component | What it does | Refrigerant state |
|---|---|---|
| Compressor | Compresses low pressure vapor | High pressure vapor out |
| Condenser | Rejects heat, condenses vapor | High pressure liquid out |
| Receiver | Stores liquid from the condenser | High pressure liquid |
| Expansion device | Drops pressure into the evaporator | Low pressure liquid and vapor mix |
| Evaporator | Absorbs heat, boils refrigerant | Low pressure vapor out |
| Accumulator | Traps liquid before the compressor | Low pressure liquid held as vapor passes |
Type 2 is taken in addition to the Core section, and both must pass; this is the proctored standard published by the EPA-approved certifying organizations under EPA Section 608.
Leak rate thresholds: when repair becomes mandatory
Mandatory leak repair on Type 2 equipment is triggered by three annual leak rate thresholds, 10%, 20%, and 30%, and the threshold depends entirely on the equipment category:
| Equipment category | Annual leak threshold | System size trigger | Mandatory repair deadline |
|---|---|---|---|
| Comfort cooling (office AC, residential AC, heat pumps) | 10% of charge per year | 50 lbs or more of refrigerant | Within 30 days of discovery |
| Commercial refrigeration (walk in coolers, display cases, reach in units) | 20% of charge per year | 50 lbs or more of refrigerant | Within 30 days of discovery |
| Industrial process refrigeration | 30% of charge per year | 50 lbs or more of refrigerant | Within 30 days of discovery |
Comfort cooling (10% threshold): Applies to systems used primarily for occupant comfort, such as residential split systems, office air conditioning, and heat pumps. A system with 100 lbs of refrigerant that loses 10 lbs per year has hit the threshold; a system that loses 11 lbs has exceeded it and requires mandatory repair.
Commercial refrigeration (20% threshold): Applies to systems that refrigerate food or product for commercial sale, such as walk in coolers, walk in freezers, commercial display cases, and reach in units.
Industrial process refrigeration (30% threshold): Applies to systems used in manufacturing and industrial processes, such as chemical plants, food processing, and industrial cold storage at larger scales.
The 50 pound trigger: Mandatory leak repair rules apply only to systems containing 50 or more pounds of refrigerant. Systems below 50 pounds are not subject to the percentage based mandatory repair obligation, though refrigerant must still be recovered before service and venting remains prohibited.
The 30 day repair rule: When a technician discovers a leak that has exceeded the applicable threshold, repair must be completed within 30 calendar days of discovering the leak. If the repair requires an industrial process shutdown, the deadline extends to 120 days. Operating a leaking system past the deadline is a Section 608 violation, and the civil penalty exceeds $69,733 per day per violation under the Clean Air Act penalty table.
Tiered leak rate summary
Comfort cooling = 10%. Commercial refrigeration = 20%. Industrial process = 30%. All require mandatory repair within 30 days and apply only to systems with 50 lbs or more of refrigerant. Identify the equipment category before selecting a leak rate answer.
The 10/20/30% tiers are the rule as it stands in the current eCFR. The 35% industrial process figure still circulating on other prep sites is the pre-2019 regulation, so any source quoting 35% is outdated.
How to leak check a high pressure system
Leak detection on a high pressure system starts with the symptoms of a low charge, before any detector is used. A low refrigerant charge is the first sign of a leak. On a fixed orifice system, low superheat readings point to a low charge. And because refrigerant and oil circulate together, refrigerant escaping at a leak point vaporizes and leaves the oil behind, so a trace of oil on a fitting, joint, or coil is a visual flag for the leak location.
The exam expects you to know the accepted leak checking methods: an electronic (halide or ultrasonic) leak detector, adding dye to the refrigerant, brushing soap solution on suspect joints and watching for bubbles, and a halide torch, whose flame turns green in the presence of halogenated refrigerant.
Pressurizing a system to leak check: use an inert gas. Nitrogen alone is preferred. If your electronic detector needs refrigerant to react to, nitrogen mixed with a trace amount of the system's designated refrigerant is acceptable. After leak checking, all of that trace mixture must be recovered before the system is opened.
Never pressurize with oxygen or compressed air
Oxygen, on its own or as compressed air, mixed with refrigerant oil under pressure is explosive. The only correct pressurizing gases are nitrogen, or nitrogen with a trace of the system's refrigerant.
Recovery vacuum requirements for high pressure systems
Recovery vacuum levels are the hardest topic on the Type 2 section. The 26.4% miss rate reported at the top of this page belongs to the evacuation and vacuum questions, against 16.4% for the rest of Type 2, and inside that group the misses concentrate on the vacuum level thresholds rather than on charging technique. Vacuum level is the one topic with two moving variables, refrigerant weight and equipment manufacture date, and it is the only place in the section where our users miss at anything like that rate. Those are practice figures rather than official exam statistics.
Type 2 recovery vacuum requirements are set by system refrigerant weight and recovery equipment manufacture date. Both variables appear on the exam, and knowing only one will lead to wrong answers.
For recovery equipment manufactured after November 15, 1993:
Systems containing less than 200 lbs of refrigerant (R-22 class): recover to 0 in. Hg — down to atmospheric pressure.
Systems containing 200 lbs or more of refrigerant (R-22 class): recover to 10 in. Hg vacuum with post-1993 equipment (4 in. Hg with pre-1993 equipment). Other high pressure refrigerants (CFC-12, R-500, R-502, R-114) at this size require 15 in. Hg with post-1993 equipment.
For recovery equipment manufactured before November 15, 1993:
Older recovery equipment carries a shallower requirement: 4 in. Hg vacuum for systems of 200 lbs or more, versus 10 in. Hg with post-1993 equipment. R-22 systems under 200 lbs stay at 0 in. Hg regardless of equipment age. The lower standard reflected the recovery equipment available at the time.
The November 15, 1993 date applies to recovery equipment manufacture, not the appliance. If the recovery equipment was manufactured after November 15, 1993, which includes virtually all equipment now in service, the post 1993 vacuum standards apply regardless of when the appliance was built.
Why vacuum matters for recovery: Pulling a vacuum ensures the maximum amount of refrigerant has been removed from the system before it is opened for service. The 15 in. Hg level is not about size alone. It belongs to the CFC-12 class (R-12, R-500, R-502, R-114) at 200 lbs or more. An R-22 class system of the same size stops at 10 in. Hg. Read the refrigerant first, the charge second, the equipment date third, in that order, and the vacuum questions stop being guesswork.
Recovery techniques the Type 2 exam tests
Recovery technique questions on the Type 2 section test the order and speed of recovery, not only the final vacuum level. Recover liquid refrigerant first. Removing refrigerant in the liquid phase is the fastest way to recover, and starting with liquid before switching to vapor speeds up every large recovery job.
Three more speed techniques appear as exam answers: keep the system pressure high and the recovery cylinder pressure low, by warming the appliance and chilling the cylinder; use short, large diameter hoses to cut friction loss; and use low loss fittings to minimize release when connecting and disconnecting.
After you reach the required vacuum, wait. Refrigerant trapped in the oil or remaining as liquid keeps vaporizing, and if system pressure rises you must resume recovery. The exam phrases this as waiting a few minutes to confirm pressure does not rise before opening the system.
Cylinder and equipment rules: never mix refrigerants in one recovery cylinder; refrigerant that has been mixed must be sent to a certified reclaimer. Never fill a recovery cylinder past 80% of its capacity by weight. Confirm what is in the system with a pressure temperature chart before you recover; the R-22 and A2L section on this page covers how each family behaves.
System dependent (passive) recovery equipment may not be used on appliances holding more than 15 lbs of refrigerant. Above that charge, self contained (active) recovery equipment is required. This 15 pound line is a recurring Type 2 question.
R-22 phaseout and the A2L refrigerant transition
R-22 has two phaseout dates, January 1, 2010 and January 1, 2020, and the Type 2 exam tests both.
January 1, 2010: production and import of R-22 for use in new air conditioning and refrigeration equipment was prohibited. From this date, new HVAC equipment could not be manufactured or imported using R-22 as the working refrigerant. R-22 already in the supply chain could still be used for servicing existing equipment.
January 1, 2020: all production and import of R-22 was prohibited. No new R-22 may be manufactured or imported in the United States. The only legal supply of R-22 after 2020 is reclaimed refrigerant, which is refrigerant recovered from existing equipment, reprocessed to AHRI 700 purity standards, and resold for use in existing R-22 systems. Reclaimed R-22 remains legal for servicing existing equipment indefinitely.
The A2L transition, replacing R-410A: R-410A, which itself replaced R-22 as the dominant residential refrigerant, is now being phased down under the AIM Act (American Innovation and Manufacturing Act of 2020). The AIM Act mandates an 85% reduction in HFC production by 2036.
2025 AIM Act phasedown: production allowances for R-410A declined sharply beginning January 1, 2025, effectively ending R-410A use in new residential and light commercial HVAC equipment. New equipment manufactured after this date primarily uses A2L refrigerants.
R-454B (Opteon XL41): the primary R-410A replacement in residential split systems. Lower GWP than R-410A, 466 against 2,088. Mildly flammable (A2L class), so it requires equipment and installation practices rated for A2L refrigerant.
R-32: lower GWP than R-410A (675 versus 2,088). Used in some equipment types as a standalone refrigerant. Also mildly flammable (A2L).
A2L safety implications for Type 2 technicians: A2L refrigerants carry a mild flammability rating. Installation and service practices for A2L systems differ from non flammable refrigerants in ventilation, ignition source control, and detector requirements.
Two R-22 dates, both are tested
January 1, 2010: R-22 banned for use in new equipment. January 1, 2020: all R-22 production and import banned. Both dates appear on the Type 2 exam.
Mandatory repair: the 30 day rule and the 50 pound trigger
The mandatory repair obligation applies only when both conditions are met at once: the system contains 50 or more pounds of refrigerant and its annual leak rate exceeds the threshold for its equipment category. Once both are met, the clock starts immediately, and the owner or operator, not the technician, is responsible for ensuring repair occurs in time.
What counts as repair: the system must be returned to within the applicable threshold leak rate. A repair that reduces leakage but still leaves the annual rate above the threshold does not satisfy the requirement. The owner must verify leak rate compliance after repair.
The 120 day industrial process exception: the repair window stretches from 30 days to 120 days in one situation only, when completing the repair requires shutting down an industrial process. No other circumstance extends the clock. Parts delays and access problems do not. If the owner will not repair, the alternative is a written retrofit or retirement plan, not a longer deadline.
Major vs nonmajor repairs, and who owns disposal
A major repair, under 40 CFR 82.152, is any maintenance, service, or repair that involves removing the compressor, condenser, evaporator, or auxiliary heat exchanger coil. Everything else is nonmajor, and the required recovery vacuum depends partly on that distinction. The exam asks for those four components by name.
The leaky system exception: if a leak is large enough that the system cannot hold the prescribed recovery vacuum, evacuate to atmospheric pressure (0 psig) before opening it. Pulling deeper would just draw air and moisture in through the leak.
Disposal: refrigerant must be recovered from a high pressure appliance before disposal, using the same evacuation levels that apply to service. The final person in the disposal chain, normally the scrap metal recycler, is responsible for making sure refrigerant was removed and must keep records documenting recovery.
EPA Type 2 study guide FAQ
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Part of the EPA 608 study guides collection
This Type 2 study guide is part of the complete EPA 608 test study guide collection, covering Core, Type 1, Type 2, Type 3, Universal, and a condensed cheat sheet for last minute review.