EPA 608 Type II Study Guide: High-Pressure Systems

Type II is the densest section of the EPA 608 exam. It covers the refrigerant systems most HVAC techs interact with every day — R-22 and R-410A split systems, commercial refrigeration cases, rooftop units — and the regulations that govern working on them. This guide covers the exam material in the order that makes it stick.

What counts as a high-pressure appliance

Type II applies to high-pressure appliances: systems charged with refrigerants that have a boiling point between -50°C and 10°C at atmospheric pressure. In practical terms, this is most of what commercial and residential HVAC techs touch.

Common Type II refrigerants:

• R-22 (HCFC — phased out for new equipment, still in existing systems)
• R-410A (HFC — dominant residential and light commercial refrigerant until R-454B transition)
• R-404A (HFC — commercial refrigeration, being replaced)
• R-407C (HFC — used in R-22 retrofit applications)
• R-507 (HFC azeotrope — low-temperature commercial refrigeration)
• R-134a (HFC — automotive and some commercial applications)
• R-452B / R-454B (HFO blends — current replacements for R-410A)

If the refrigerant does not fall into the low-pressure category (R-11, R-113, R-123 — Type III) and is not in a small hermetically sealed appliance (Type I), it is almost certainly Type II.

The venting prohibition

Recovery is not optional. Section 608 prohibits intentional venting of any refrigerant covered by the regulation. "The system is old, it's going to leak anyway" is not a legal defense. "It's only 3 pounds" is not a legal defense.

The prohibition applies to all technicians. Violations can result in fines up to $44,539 per day per violation for willful noncompliance. The exam tests whether you know this number.

Recovery requirements

Before opening any high-pressure system for service or disposal, the refrigerant must be recovered.

Equipment requirements

Recovery equipment used for Type II systems must be certified by an EPA-approved testing organization (such as UL or ETL) to meet EPA performance standards. This is different from Type I, where a simpler certification pathway exists.

The equipment must be in proper working order. Using malfunctioning recovery equipment that fails to meet recovery standards is a violation.

Evacuation levels

The required evacuation depth depends on the size of the system and when the recovery equipment was manufactured.

For recovery equipment manufactured after November 15, 1993:

System charge	Required evacuation
Less than 200 lbs	4 inches Hg vacuum
200 lbs or more	23 inches Hg vacuum
Very high-pressure (R-410A, R-404A, R-507)	0 psig

For recovery equipment manufactured before November 15, 1993:

System charge	Required evacuation
Less than 200 lbs	0 inches Hg vacuum (atmospheric)
200 lbs or more	15 inches Hg vacuum
Very high-pressure	0 psig

The very high-pressure category (R-410A, R-404A, R-507) uses a 0 psig standard because these refrigerants operate at high pressures relative to atmospheric — pulling a deep vacuum risks damaging compressors and other system components.

Memorize these numbers. The exam will present a scenario — "A technician is recovering R-410A from a 150-pound system using equipment manufactured in 2018. What is the required evacuation level?" — and you need the right number reflexively.

Refrigerant recovery cylinders

Recovery cylinders are a high-frequency exam topic. The rules are specific.

Color code: Standard recovery cylinders are gray with a yellow top. This identifies them as recovery/recycle use only. Do not confuse with virgin refrigerant cylinders, which have refrigerant-specific colors.

Fill limit: Cylinders must not exceed 80% capacity by weight (liquid fill). Overfilling creates a hydraulic pressure hazard — refrigerant has no compressible space if the temperature rises.

DOT certification: Cylinders must be DOT-approved for the refrigerant being stored. Different DOT specifications (e.g., DOT-4BA, DOT-4BW) have different retesting intervals. Most cylinders require retesting or replacement every 5 years. Some DOT-4BW cylinders qualify for a 12-year interval under certain conditions.

Cylinder condition: Damaged, corroded, or cylinders without readable DOT markings must be taken out of service. You cannot remove or falsify DOT markings on a cylinder.

Leak rate requirements for large systems

For appliances containing more than 50 pounds of refrigerant, EPA Section 608 imposes mandatory leak rate monitoring and repair obligations.

Leak rate thresholds

If a system's annual leak rate exceeds the threshold for its equipment type, the owner must repair the leak within 30 days (or document a plan for repair if parts are unavailable):

• Comfort cooling (chillers, large rooftop units): 15% annual leak rate
• Commercial refrigeration: 35% annual leak rate
• Industrial process refrigeration: 35% annual leak rate

Annual leak rate is calculated by dividing the total refrigerant added to the system over 12 months by the full charge of the system, then multiplying by 100.

What triggers the repair clock

Adding refrigerant to a system that contains more than 50 pounds initiates the leak rate tracking period. If subsequent additions push the calculated annual rate over the threshold, the 30-day repair window opens.

Record-keeping requirement: Owners of systems with more than 50 pounds of refrigerant must maintain records of the amount and type of refrigerant purchased and added to each system. These records must be kept for 3 years and be available for EPA inspection.

Retrofit and retirement threshold

If a leaking system cannot be economically repaired and it contains a refrigerant being phased out, the owner may be required to retrofit the system to use a different refrigerant or retire the equipment rather than continue adding refrigerant to a chronic leak.

Refrigerant transfers: recover, recycle, reclaim

The exam tests whether you know the distinction between these three terms and when each applies.

Recovery: Removing refrigerant from a system without testing or processing it, storing it in an approved container. This is the first step whenever you open a system.

Recycling: Cleaning recovered refrigerant using oil separation and single or multiple passes through filter-driers to reduce moisture, acidity, and particulates. Recycled refrigerant can be returned to the same owner's equipment — not to another owner without reclaim.

Reclaim: Reprocessing recovered refrigerant to ARI Standard 700 purity (the same standard as virgin refrigerant). Reclamation must be done by an EPA-certified reclaimers. Reclaimed refrigerant can be sold or transferred to any owner.

The practical rule: refrigerant stays with the same owner unless it has been reclaimed. A technician who recovers R-22 from one customer's system cannot legally charge that refrigerant into a different customer's system.

Brazing and leak testing

The exam includes questions on proper brazing and leak detection procedures because improper technique leads to leaks.

Nitrogen pressure testing: Before charging a system after brazing, the system should be pressurized with dry nitrogen to check for leaks. Never use oxygen or any oxidizing gas — this is an explosion risk. Never use refrigerant as a leak detection gas if the leak is into an area with an open flame.

Acceptable leak testing methods: Electronic leak detectors, halide torch (for halogenated refrigerants), soap bubbles, nitrogen/trace gas with a gas detector. The method must be appropriate for the refrigerant — halide torches cannot be used with flammable refrigerants (R-600a, R-290).

Standing pressure test: After nitrogen pressure testing, if the system holds pressure without drop over a set period, the brazed joints are leak-free.

Technician certification

To recover refrigerant from high-pressure Type II systems, technicians must hold a valid EPA 608 certification — either Type II or Universal. There is no grace period for working on systems while waiting for certification.

Certifications do not expire. If you passed the exam in 1993, your certification is still valid today. However, employers may have their own continuing education requirements separate from EPA compliance.

High-probability exam topics: Type II

Drill these until they are automatic:

• Evacuation levels for post-1993 equipment (4 in Hg for <200 lbs, 23 in Hg for ≥200 lbs, 0 psig for very high-pressure)
• Recovery cylinder color (gray/yellow), fill limit (80%), retesting interval (5 years typical)
• Leak rate thresholds (15% comfort cooling, 35% commercial/industrial) and the 50-pound trigger
• Three-year record-keeping requirement for large system refrigerant additions
• Recover vs. recycle vs. reclaim — when each is required
• $44,539 per day fine for willful venting
• Nitrogen (not oxygen) for pressure testing after brazing

The difference between Type II and Universal

Universal certification includes Type I, Type II, and Type III. If your work includes any low-pressure systems (large centrifugal chillers using R-123, for example), you need Universal. If you exclusively work on high-pressure systems, Type II certification is sufficient for that work.

Most commercial HVAC techs pursue Universal because the cost and time difference is minimal and it avoids any question about coverage.

Ready to test yourself

The free practice test at epa608study.com includes a full Type II section alongside Core, Type I, and Type III. Run through it before sitting for the real exam.

Full exam prep — all four sections, 225 questions, 52 lessons — is $14.99 one-time. No subscription, no upsells. Offline-capable. English and Spanish.

Type II carries more exam weight than any other section. Own it.