EPA 608 Type II Answer Explanations
Type II certification covers medium-, high-, and very-high-pressure appliances under 40 CFR § 82.161(a)(1)(ii), except small appliances, MVACs, and MVAC-like appliances. This page helps learners preparing for Type II or Universal certification review the reasoning behind their practice answers. The section brings together appliance classification, refrigerant recovery, leak-related requirements, and the behavior of components during service. It rewards careful reading: the equipment description can matter just as much as the refrigerant name.
When reviewing a recovery question, identify the appliance pressure category, full charge, and the manufacture or import date of the recovery equipment. Those details determine which table entry applies. Do not assume that every major repair has the same vacuum target, or confuse a recovery endpoint with the deeper evacuation used for dehydration. For leak questions, first identify which refrigerant and appliance category the question describes before comparing any rates or deadlines.
Use the explanations below to diagnose a missed concept rather than memorize an answer letter. Trace a wrong answer back to the detail you overlooked, and consult the related rule when the distinction is regulatory. The Type II study guide organizes the topics into a review sequence; the matching practice test lets you check your understanding again without the answer text in view.
Most-missed topics
Use these review prompts to catch common mix-ups in this question set; they are not a ranking based on learner scores.
- Recovery-table selection: Pressure category, full charge, and recovery-equipment manufacture or import date determine the applicable Table 1 entry.
- Equipment date: The recovery-table date refers to recovery equipment, not the service date or refrigerant introduction date.
- Major repairs: Removing a compressor, condenser, evaporator, or auxiliary heat exchanger coil is major maintenance, service, or repair; it does not set one universal recovery target.
- Recovery versus dehydration: A dehydration target is not the EPA Table 1 recovery limit; use the applicable requirement for the task.
Sources: EPA Section 608 definitions and 40 CFR § 82.156 recovery requirements. See each answer for related study material.
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Type II
What is the purpose of a correctly selected pressure-relief device?
Correct answer: D. Protect against excessive pressure.
Pressure-relief protection must match the equipment design, applicable code, and manufacturer instructions. Do not assume every HVAC/R appliance uses the same type of relief valve.
Section 608 recovery equipment manufactured or imported on or after November 15, 1993 must be certified by:
Correct answer: C. an EPA approved laboratory
EPA-approved organizations certify Section 608 recovery/recycling equipment against applicable performance requirements. EPA lists AHRI and UL for this program. Older equipment has separate grandfathering conditions. Source: 40 CFR 82.158 and EPA equipment-certification guidance.
When using a recovery unit on a system containing 100 lbs. of R-410A it must be evacuated to
Correct answer: A. 0 inches of Mercury
R-410A is a high-pressure refrigerant, and EPA Section 608 recovery tables require evacuation only to 0 in. Hg (atmospheric) for high-pressure appliances containing less than 200 lbs of charge when using equipment built on or after Nov 15, 1993. The deeper vacuums (4, 10, 15 in. Hg) listed here apply to other appliance categories, not a 100 lb R-410A system.
Under 40 CFR 82.157, when refrigerant is added to a covered appliance exceeding its leak-rate threshold, what is the usual repair deadline if no industrial shutdown or extension applies?
Correct answer: A. 30 days.
The usual repair deadline is 30 days. The rule allows 120 days if an industrial process shutdown is required and provides specific extension procedures. There is no general 90-day scheduling allowance. This Section 608 rule covers appliances with a full charge of at least 50 pounds of ozone-depleting refrigerant. Source: 40 CFR 82.157(a), (d), and (f).
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Using recovery equipment manufactured or imported on or after November 15, 1993, a high-pressure appliance with a full charge of 210 lbs. of R-407C must be recovered to what Table 1 level before opening for a major repair?
Correct answer: B. 10 inches of vacuum
The required level is 10 inches Hg vacuum for a high-pressure appliance with a full charge of 200 pounds or more using recovery equipment manufactured or imported on or after November 15, 1993. The older-equipment column specifies 4 inches Hg vacuum, not 0. The date refers to recovery equipment, not the service date or the refrigerant's introduction. Source: 40 CFR 82.156(a), Table 1.
EPA regulations state that removal of which component constitutes a "major repair"?
Correct answer: B. Compressor
A major repair involves removal of the compressor, condenser, evaporator, or auxiliary heat exchanger coil. The definition also covers uncovering an opening of more than 4 square inches of flow area for more than 15 minutes. Use the applicable Table 1 recovery level based on appliance pressure category, full charge, and recovery-equipment manufacture/import date. Major repair alone does not establish one universal deep-vacuum target. Source: 40 CFR 82.152 and 82.156(a).
A refrigerant sensor which will sound an alarm and automatically start a ventilation system in occupied equipment rooms falls under ASHRAE Standard;
Correct answer: A. 15
ASHRAE Standard 15 governs the safety of refrigeration systems, including machinery-room sensors, alarms, and emergency ventilation requirements. ASHRAE 34 covers refrigerant safety classifications (A1, B2, etc.) and 90.1 covers building energy efficiency, so they are related but address different topics. Don't confuse Standard 15 (safety) with Standard 34 (refrigerant naming/classification).
Under 40 CFR 82.156(a)(3), which disposal-recovery records must technicians keep for appliances with a full charge of more than 5 but less than 50 pounds?
Correct answer: B. Per-appliance recovery details, monthly totals by refrigerant type, and reclamation/destruction transfer details.
Keep the company name, appliance location, recovery date and refrigerant type; monthly recovered totals by type; and quantities/types transferred for reclamation or destruction, recipient, and transfer date. Retain these records for three years. Source: 40 CFR 82.156(a)(3).
Which instrument is appropriate for verifying a manufacturer's deep-vacuum dehydration target?
Correct answer: C. An electronic micron gauge.
Dehydration removes moisture and noncondensables after refrigerant recovery. Use a micron gauge and the manufacturer's evacuation and standing-vacuum criteria. A dehydration target is not the EPA Table 1 recovery limit.
Which of the following refrigerants is classified as a very high-pressure refrigerant?
Correct answer: B. R-744
R-744 (carbon dioxide) is classified as a very high-pressure refrigerant; its critical temperature is around 88°F and operating pressures reach well over 1,000 psig. R-410A and R-22 are high-pressure refrigerants but operate at much lower pressures, while R-123 is a low-pressure refrigerant that runs in a vacuum on the low side.
Under Table 1, a high-pressure appliance with a full charge of less than 200 lbs. of an HCFC or HFC refrigerant must be recovered to:
Correct answer: D. 0 inches of vacuum
The required level is 0 inches Hg vacuum (atmospheric pressure) for high-pressure appliances with a full charge below 200 pounds in both recovery-equipment date columns. The 15-inch target applies to medium-pressure appliances with 200 pounds or more using newer recovery equipment. Source: 40 CFR 82.156(a), Table 1.
If a covered leaking appliance will not be repaired, what is the usual retrofit-or-retire requirement?
Correct answer: A. Plan within 30 days; complete within one year.
If the owner chooses retrofit or retirement instead of repair, the usual rule is to develop the plan within 30 days and complete it within one year. Limited extensions or relief can apply in defined circumstances. The 30-day deadline is for the plan, not universal completion of the entire retrofit.
For a 50-pound-or-larger appliance covered by Section 608 leak-repair requirements, which records must document whether a repair worked?
Correct answer: A. The dates, methods, locations, and results of the initial and follow-up verification tests.
For a covered 50+ lb ODS appliance that exceeds the trigger rate, the repair record must document the initial and follow-up verification tests, including when and how they were performed, the repaired leak locations tested, and the results. A separate chronic-leak report is triggered if the appliance leaks 125% or more of its full charge in a calendar year.
A crankcase heater is often used to prevent refrigerant from mixing with compressor oil during periods of
Correct answer: A. Low ambient temperature
A crankcase heater warms the compressor oil during off-cycles in cold weather to drive refrigerant out of the oil. At low ambient temperatures, refrigerant migrates to the coldest spot, which is often the compressor crankcase, where it dissolves into the oil and can cause foaming, slugging, and bearing damage on startup.
Under Section 608, an industrial process refrigeration appliance with 50 pounds or more of ozone-depleting refrigerant triggers corrective action when its annualized leak rate exceeds:
Correct answer: C. 30%
The trigger is a leak rate above 30%, not simply reaching 30%. Repair and verification requirements or a compliant retrofit/retirement plan then apply. Source: 40 CFR 82.157(c).
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Under Section 608, an Industrial Process Refrigeration (IPR) system containing 50 pounds or more of ozone-depleting refrigerant must be repaired when the annual leak rate exceeds:
Correct answer: C. 30%
IPR systems covered by Section 608 must be repaired when the annual leak rate exceeds 30%. Commercial refrigeration uses 20%, and comfort cooling and other appliances use 10%. For Section 608 leak repair, the appliance must contain 50 pounds or more of ozone-depleting refrigerant.
Refrigerants CFC-12, HCFC-22, and HFC-134a are all classified as Type ________ substances.
Correct answer: C. A-1
Under ASHRAE Standard 34, R-12, R-22, and R-134a are all Class A1: 'A' means low toxicity, '1' means no flame propagation. B-class refrigerants (B1, B2) are higher toxicity (e.g., R-123 is B1, ammonia is B2L). Knowing the safety class drives machinery-room and ventilation requirements.
Under the 2026 AIM Act program, what annual leak-rate threshold applies to a covered HFC appliance categorized as comfort cooling?
Correct answer: B. 10%
A covered HFC appliance categorized as comfort cooling uses a 10% annual leak-rate threshold under 40 CFR 84.106. The AIM Act program generally begins at 15 pounds of HFC or certain substitutes with GWP above 53, but residential and light-commercial AC and heat-pump appliances are excluded.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
What happens to a refrigerant that is heated above the saturation temperature?
Correct answer: A. It remains in the vapor state.
At a given pressure, vapor above its saturation temperature is superheated. At saturation, refrigerant may be saturated liquid, saturated vapor, or a liquid-vapor mixture.
Using recovery equipment manufactured or imported on or after November 15, 1993, a medium-pressure appliance with a full charge of 200 lbs. or more must be recovered to what Table 1 vacuum level?
Correct answer: D. 15" Hg
The required level is 15 inches Hg vacuum. Medium-pressure appliances with a full charge of 200 pounds or more have a 4-inch target for pre-November-15-1993 recovery equipment and a 15-inch target for equipment manufactured or imported on or after that date. Source: 40 CFR 82.156(a), Table 1.
Non-condensables will cause;
Correct answer: D. High discharge pressure
Non-condensables (mainly air) collect in the top of the condenser and take up space that should be holding refrigerant vapor that is condensing, which raises head pressure and discharge pressure. The result is reduced capacity, higher amp draw, and elevated compressor discharge temperature that can break down oil.
When planning liquid recovery, which location should be considered?
Correct answer: A. An approved access point where liquid has collected.
Liquid may collect in a receiver, condenser, or other low point depending on system design and conditions. Identify trapped sections and use the manufacturer's recovery connections and procedure.
Does mixing nitrogen with a regulated refrigerant automatically allow the mixture to be vented?
Correct answer: A. No; adding nitrogen does not create a general venting exemption.
Do not assume a refrigerant-containing test mixture can be released merely because nitrogen was added. Follow the applicable venting rules and an approved recovery procedure for the mixture. Pure nitrogen is distinct from nitrogen deliberately mixed with a regulated refrigerant. Source: 40 CFR 82.154(a).
📖 Related rule: § 82.152 — Definitions (recover, recycle, reclaim)
What should guide pressure leak-testing a newly installed split system?
Correct answer: D. Use the manufacturer's approved dry-nitrogen procedure and pressure limits.
Use regulated dry nitrogen with appropriate relief protection and compatible test equipment. Follow the manufacturer's sequence and rated test limits; adding refrigerant as a tracer is not universally necessary and does not authorize venting.
📖 Related rule: Core Study Guide — Refrigerant Cylinders and Handling
When may the leaking-component exception to EPA Table 1 apply?
Correct answer: A. Leaks prevent reaching the Table 1 level or would substantially contaminate the recovered refrigerant.
Isolate leaking and non-leaking components where possible. Recover non-leaking components to Table 1 and leaking components to the lowest attainable level without substantial contamination, no higher than 0 psig. Source: 40 CFR 82.156(a)(2).
When should piercing-type valves be used, and what is a common problem with them?
Correct answer: A. Use only when no other access is available; they tend to leak if left installed.
Temporary piercing access fittings can leak if left in service. Use them only as intended and finish the repair using the manufacturer's approved permanent closure or service fitting. Not every product sold as a piercing fitting has identical approval conditions.
Before charging a new system with refrigerant, what should be done?
Correct answer: B. Pressurize with nitrogen, an inert gas, and leak check.
Nitrogen is dry and inert, so it pressurizes new lines for leak testing without reacting with system materials, introducing moisture, or combusting. Compressed air contains moisture and oxygen — bad for the system long-term and dangerously combustible when mixed with refrigerant oils. Oxygen with refrigerant oil under pressure is explosive.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
When selecting a tracer for a manufacturer's approved leak-test procedure, what matters?
Correct answer: D. Compatibility, detector suitability, and applicable recovery/venting rules.
Use only the procedure and tracer approved for the system. A hydrocarbon tracer is flammable and not generally approved. Nitrogen with a tracer is not automatically exempt from venting restrictions.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Which statement about leak-detection tools is correct?
Correct answer: C. Compatible electronic detectors can find leak areas, and bubble solution can confirm accessible locations.
Choose methods compatible with the refrigerant and equipment. Both electronic detection and bubble testing can help pinpoint leaks; neither a stain nor a single operating reading proves a leak by itself.
📖 Related rule: Core Study Guide — Refrigerant Cylinders and Handling
Traces of oil around a sight glass inlet fitting of a refrigeration system might be the indication of:
Correct answer: A. A leak
Oil traces can suggest a refrigerant leak, but they may also come from earlier service or another source. Confirm the suspected location using an appropriate leak-detection method.
Describe ways you can visually look for leaks.
Correct answer: A. Look for oil traces and use appropriate bubble testing to confirm accessible leaks.
Visual oil traces can guide inspection. High superheat can have several causes and is not visual proof of a leak. Confirm the diagnosis rather than adding refrigerant based only on one symptom.
Type II classification, as identified by EPA, applies to what equipment?
Correct answer: D. High- and very-high-pressure appliances, except small appliances and MVACs.
Type II covers this equipment category; Universal also covers it. The small-appliance exception depends on factory construction and charge, not simply a rule that every appliance at five pounds or less is Type I. Source: 40 CFR 82.161.
Under Section 608, what are the current leak-rate thresholds for comfort-cooling and industrial-process-refrigeration appliances containing 50 pounds or more of ozone-depleting refrigerant?
Correct answer: A. Comfort cooling: 10%; industrial process refrigeration: 30%.
For Section 608 appliances containing 50 pounds or more of ozone-depleting refrigerant, comfort cooling uses a 10% annual threshold and industrial process refrigeration uses 30%. Commercial refrigeration is a separate category at 20%.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Which HCFC was widely used in residential and commercial air conditioning before its U.S. production/import phaseout?
Correct answer: B. R-22
R-22 was widely used in air conditioning. Restrictions for new equipment began in 2010 and ordinary production/import ended in 2020. Existing R-22 equipment may still be serviced using lawful supplies; the refrigerant was not simply outlawed for all uses.
Under Table 1, a non-small-appliance R-12 system with a full charge below 200 pounds requires what recovery level using equipment manufactured or imported on or after November 15, 1993?
Correct answer: C. 10 inches Hg
R-12 is medium-pressure under the current Section 608 definitions. For a medium-pressure appliance below 200 pounds, newer recovery equipment must reach 10 inches Hg vacuum; older equipment has a 4-inch target. Source: 40 CFR 82.152 and 82.156(a), Table 1.
What is the purpose of the filter drier and when should it be changed?
Correct answer: B. It removes moisture and other contaminants; replace it as specified by the manufacturer and service condition.
Filter-driers remove moisture and capture contaminants. Replacement is commonly part of opening or repairing a circuit, but follow the specific manufacturer's requirements rather than opening an otherwise sealed system on an invented universal schedule.
Industrial process refrigeration equipment containing 50 pounds or more of ozone-depleting refrigerant requires repair when the annual leak rate exceeds ________ %.
Correct answer: B. 30
Industrial process refrigeration uses a 30% annual leak threshold. Commercial refrigeration is 20%, while comfort cooling and other covered Section 608 appliances use 10%.
How can you tell through a sight glass if there is excess moisture in the system?
Correct answer: B. The moisture indicator on the sight glass changes color.
Read the moisture indicator against its manufacturer's legend and operating conditions. Color meanings and acceptable moisture levels are product-specific. A wet indication calls for investigation and the prescribed corrective service, not a diagnosis from bubbles alone.
Comfort-cooling and other appliances containing 50 pounds or more of ozone-depleting refrigerant require repair when the annual leak rate exceeds ________ %:
Correct answer: A. 10
Comfort cooling and 'all other' appliances covered by Section 608 use a 10% annual leak threshold. Commercial refrigeration is 20%, and industrial process refrigeration is 30%.
During dehydration after refrigerant recovery, how can repeated evacuation with approved dry-nitrogen breaks help with trapped moisture?
Correct answer: A. It interrupts deep vacuum so frozen moisture can warm before evacuation resumes.
Rapid evaporation can cool free water enough to freeze it. Approved controlled heat and evacuation procedures, which may include dry-nitrogen breaks, can help. Follow equipment limits and do not confuse dehydration with recovering a refrigerant-containing charge.
Which component, when fitted, is specifically designed to store liquid refrigerant?
Correct answer: B. Receiver (when applied)
A receiver stores liquid refrigerant. Liquid can also be present in the condenser, evaporator, piping, and trapped sections; its actual distribution depends on the system and conditions.
Foaming at start-up may be found in what component? What does this mean?
Correct answer: B. Refrigerant in compressor oil causes foaming; a crankcase heater helps prevent migration.
When a system sits idle, refrigerant migrates and condenses into the cooler compressor crankcase oil. At startup, pressure drops and the dissolved refrigerant flashes off, foaming the oil and risking liquid slugging or oil pump-out. A crankcase heater keeps the oil warmer than the rest of the system so refrigerant migrates elsewhere instead.
What are preferred ways to measure a deep vacuum?
Correct answer: B. Use a calibrated micron gauge connected to the system.
An ordinary compound gauge does not provide adequate resolution for verifying a deep dehydration vacuum. Use a suitable micron gauge and the manufacturer's evacuation and standing-vacuum criteria.
Section 608 owner/operator service recordkeeping under 40 CFR 82.157 applies to covered ozone-depleting-refrigerant appliances with a full charge of how many pounds or more?
Correct answer: D. 50 pounds
The threshold for this Section 608 program is 50 pounds or more of an ozone-depleting refrigerant. This is not a blanket exemption for smaller equipment: the AIM Act and disposal rules have separate applicability and record requirements. Source: 40 CFR 82.157(a), (l).
What do inches HG stand for?
Correct answer: C. Inches of mercury
Hg is the chemical symbol for mercury. Inches Hg can describe absolute pressure or gauge vacuum, so the reference must be stated. As vacuum deepens, absolute pressure decreases while an inches-Hg-vacuum reading increases.
What must be done when leaks prevent reaching Table 1 or would substantially contaminate recovered refrigerant?
Correct answer: B. Isolate sections where possible and meet the leaking/non-leaking component recovery requirements.
Isolate leaking and non-leaking components where possible. Recover non-leaking components to Table 1; recover leaking components to the lowest level attainable without substantially contaminating the refrigerant, no higher than 0 psig. The exception is not automatic permission to stop at 0 psig. Source: 40 CFR 82.156(a)(2).
What establishes the final dehydration vacuum and standing-test acceptance criteria?
Correct answer: C. The equipment manufacturer's service procedure.
Follow the manufacturer's pressure, hold-time, and pressure-rise criteria. A 500-micron target is common in some service procedures, but EPA recovery limits are separate, and a single vacuum reading alone does not establish dryness.
Why should you never start a hermetic compressor when under deep vacuum?
Correct answer: A. Motor winding could be damaged
Energizing a hermetic motor in a vacuum can cause insulation breakdown and arcing that damages the windings. Valve or shaft damage is not the primary risk.
The condition and state of refrigerant entering the receiver is:
Correct answer: C. High-pressure liquid from the condenser.
The receiver receives liquid from the condenser. Actual subcooling depends on system design and operating conditions; it is not guaranteed by the component name.
What is a receiver, where is it located and what is the state of the refrigerant after leaving the receiver?
Correct answer: A. After the condenser; its outlet normally supplies high-pressure liquid.
The receiver stores liquid between the condenser and the metering device. Do not assume its contents or outlet always have a fixed amount of subcooling.
What is the liquid line?
Correct answer: C. Line between the condenser and the metering device
After the condenser, refrigerant is high-pressure liquid traveling to the metering device (TXV/cap tube) — that segment is the "liquid line." Compressor-to-condenser is the discharge line; evaporator-to-compressor is the suction line. Naming each line by its location helps you reason about its expected pressure and state.
What criteria apply to Section 608 recovery equipment manufactured or imported on or after November 15, 1993?
Correct answer: A. EPA-approved third-party certification and applicable recovery-performance and low-loss-fitting requirements.
Follow the applicable requirements in 40 CFR 82.158. EPA lists AHRI and UL for Section 608 certification. The equipment date changes some Table 1 targets, not all of them; low-pressure and several other rows are the same in both columns.
Under Table 1, how many inches Hg vacuum are required for an R-22 appliance with a full charge of 200 pounds or more using recovery equipment manufactured or imported on or after November 15, 1993?
Correct answer: C. 10
R-22 is high-pressure under Section 608. This row requires 10 inches Hg vacuum with newer recovery equipment and 4 inches with pre-November-15-1993 equipment. The threshold includes exactly 200 pounds. Source: 40 CFR 82.156(a), Table 1.
What are considered “major” repairs according to the EPA?
Correct answer: B. Removal of the compressor, condenser, evaporator, or auxiliary heat exchanger.
A major repair involves removal of the compressor, condenser, evaporator, or auxiliary heat exchanger coil. The definition also covers uncovering an opening of more than 4 square inches of flow area for more than 15 minutes. Use the applicable Table 1 recovery level based on appliance pressure category, full charge, and recovery-equipment manufacture/import date. Major repair alone does not establish one universal deep-vacuum target. Source: 40 CFR 82.152 and 82.156(a).
What can you do if you can’t reach the required evacuation levels on leaky equipment?
Correct answer: B. Recover leaking sections to the lowest attainable level without substantial contamination, no higher than 0 psig.
Isolate leaking and non-leaking components where possible. Recover non-leaking components to Table 1; recover leaking components to the lowest level attainable without substantially contaminating the refrigerant, no higher than 0 psig. The exception is not automatic permission to stop at 0 psig. Source: 40 CFR 82.156(a)(2).
What are steps taken before using recovery equipment?
Correct answer: A. Verify compatibility, valves, cylinder capacity, and the manufacturer's pre-use checks.
Inspect the equipment, hoses, fittings, and compatible recovery cylinder; check remaining cylinder capacity and follow the pre-use checklist. Check oil only where the recovery design requires it and capture residual refrigerant rather than venting it.
What types of hoses and couplings should be used during the recovery process?
Correct answer: A. Quick couplers, self-sealing hoses, and hand valves to minimize release.
Use low-loss fittings: quick-disconnect couplers, self-sealing hoses, and hand valves at the connections. These minimize the small refrigerant release that happens every time a hose is connected or disconnected. Garden hoses, plain rubber tubing, and open copper lines aren't rated for refrigerant pressure and would dump refrigerant or pull air into the system.
What common contaminants can be found in the oils?
Correct answer: A. Particulates, acids, and moisture.
Compressor oil typically becomes contaminated with metal particulates from wear, acids from refrigerant breakdown (especially after burnouts), and moisture from inadequate evacuation or leaks. Filter-driers and acid test kits target exactly these three. Helium and sand aren't realistic system contaminants.
Why can a refrigerant-cooled hermetic recovery compressor overheat near the end of recovery?
Correct answer: B. The unit depends on refrigerant flow through the compressor for cooling.
In a design that relies on refrigerant flow for motor cooling, reduced flow can reduce cooling. Follow the recovery unit's operating limits and thermal-protection instructions; compressor cooling arrangements are not identical across products.
If switching from recovering one refrigerant to another, what steps must be taken before recovering the new refrigerant?
Correct answer: A. Capture residual refrigerant and prepare filters and equipment per the manufacturer's changeover procedure.
Prevent carryover when switching refrigerants. Follow the manufacturer's clearing, filter, and evacuation procedure, capturing residual refrigerant rather than venting it. Keep refrigerants separate; reclaimability of an accidental mixture depends on its contents and the reclaimer.
📖 Related rule: § 82.152 — Definitions (recover, recycle, reclaim)
Describe ways to speed up the recovery.
Correct answer: A. Cool the recovery cylinder, warm the appliance, and recover liquid through the liquid line.
Manufacturer-approved temperature management, short suitable hoses, and bulk-liquid recovery can improve recovery speed. Avoid uncontrolled heating and always monitor cylinder weight, pressure, and equipment limits.
Under Section 608, when may recovered refrigerant from a stationary appliance be reused without reclamation (excluding MVACs and MVAC-like appliances)?
Correct answer: B. It may return to the same appliance or another appliance owned by the same person.
It may be returned to the same appliance or another appliance owned by the same person, subject to suitability and other applicable requirements. Sale for use by a different owner generally requires reclamation by an EPA-certified reclaimer. Source: 40 CFR 82.156(h) and 82.154(d).
📖 Related rule: § 82.152 — Definitions (recover, recycle, reclaim)
Where should you remove the refrigerant in a system that has a condenser below the receiver?
Correct answer: A. From the condenser outlet
When the condenser sits below the receiver, refrigerant should be recovered from the condenser outlet because liquid pools at the lowest point. Drawing from there pulls liquid first, which is much faster than recovering vapor from a higher port.
In a hermetic high-pressure system, excessive superheat and oil traces around fittings are signs of:
Correct answer: B. A refrigerant leak
Oil traces and abnormal superheat can suggest a leak or undercharge, but do not prove either. Diagnose and confirm the leak with suitable methods and follow equipment instructions before corrective charging.
Before charging or recharging a high-pressure system, the technician should:
Correct answer: A. Pressurize and leak-check the system
Follow the manufacturer's leak-test, repair, evacuation, and charging procedure. Regulated dry nitrogen is commonly used for pressure testing. Do not assume every refrigerant addition is automatically unlawful or that a refrigerant tracer is always required.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
For pressure-leak testing a high-pressure system, the most preferred gas is:
Correct answer: C. Regulated dry nitrogen, using the manufacturer's approved procedure.
Dry nitrogen with suitable pressure regulation and relief protection is commonly used for pressure leak testing. Do not use oxygen or compressed air. Tracer selection, where specified, must be compatible and does not authorize venting regulated refrigerant.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
For industrial process refrigeration appliances containing 50 pounds or more of ozone-depleting refrigerant, the allowable annual leak rate is:
Correct answer: C. 30%
For Section 608 appliances with a full charge of 50 pounds or more of ozone-depleting refrigerant, the industrial-process-refrigeration trigger is above 30% annually. Commercial refrigeration uses 20%; comfort cooling and other covered categories use 10%. These are corrective-action triggers, not allowances to deliberately vent. Source: 40 CFR 82.157.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
For comfort cooling and other appliances containing 50 pounds or more of ozone-depleting refrigerant, the allowable annual leak rate is:
Correct answer: B. 10%
For Section 608 appliances with a full charge of 50 pounds or more of ozone-depleting refrigerant, comfort cooling and other covered categories have a 10% annual trigger. Commercial refrigeration currently uses 20%, and industrial process refrigeration 30%; 20% is not merely a historical figure. Source: 40 CFR 82.157.
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Under Section 608, owners/operators of covered appliances with at least 50 pounds of ozone-depleting refrigerant must keep required leak-repair records:
Correct answer: B. Be kept by the owner/operator and made available to EPA on request.
Keep applicable service, leak inspection, repair, and verification records and make them available to EPA as required. The threshold includes exactly 50 pounds. Source: 40 CFR 82.157(l).
Owners may receive an extension on the timeframe to repair a leak when:
Correct answer: B. Needed parts are unavailable or industry/safety codes prevent immediate repair.
Section 608 extensions require qualifying circumstances and the specified documentation and request to EPA. Examples include unavailable required components and conflicting regulatory requirements. Being busy or choosing a convenient shutdown date is not a blanket extension. Source: 40 CFR 82.157(f).
📖 Related rule: § 82.157 — Appliance Maintenance and Leak Repair
Recovery from a high-pressure system can be sped up by:
Correct answer: B. Recovering liquid at the beginning of the recovery process.
Bulk-liquid recovery can be faster than recovering the entire charge as vapor. Use the manufacturer's designated connections, compatible equipment, and cylinder fill limits; liquid distribution depends on the system.
Other ways to speed recovery include:
Correct answer: A. Heating the appliance and chilling the recovery cylinder.
Approved appliance warming and recovery-cylinder cooling can improve the pressure difference. Do not use flames or uncontrolled heat. Monitor equipment ratings, cylinder pressure, and permitted fill throughout recovery.
To minimize cross-contamination when a recovery/recycling machine that previously held one refrigerant is used with a different refrigerant, you should:
Correct answer: B. Capture residual refrigerant and prepare filters and equipment per the manufacturer's changeover procedure.
Prevent carryover when switching refrigerants. Follow the manufacturer's clearing, filter, and evacuation procedure, capturing residual refrigerant rather than venting it. Keep refrigerants separate; reclaimability of an accidental mixture depends on its contents and the reclaimer.
After reaching the required recovery vacuum, a technician should:
Correct answer: B. Wait a few minutes and watch for a pressure rise from remaining refrigerant.
After reaching the recovery target, isolate and observe pressure as directed by the recovery procedure. Remaining liquid or refrigerant dissolved in oil can cause pressure rebound, requiring further recovery. Leaks and temperature changes can also affect the reading; investigate rather than assume every rise has one cause.
Using recovery equipment manufactured or imported on or after November 15, 1993, a high-pressure appliance with a full charge of 200 pounds or more of refrigerant being opened for a major repair must be evacuated to:
Correct answer: B. 10 inches of mercury vacuum
The required level is 10 inches Hg vacuum for a high-pressure appliance with a full charge of 200 pounds or more using recovery equipment manufactured or imported on or after November 15, 1993. The 15-inch target belongs to medium-pressure appliances with the same charge size and equipment date. Source: 40 CFR 82.156(a), Table 1.
A "major" repair on a high-pressure appliance is one that involves:
Correct answer: A. Replacing a compressor, condenser, evaporator, or auxiliary heat exchanger.
Removing the listed components is a major repair under Section 608. The applicable Table 1 recovery target depends on the appliance category, charge, and equipment date. A non-major repair has different treatment only when the conditions of the relevant exception are met. Source: 40 CFR 82.152 and 82.156.
Except when permanently attached as a pump-out unit, system-dependent recovery equipment may not be used on appliances with a full charge greater than:
Correct answer: B. 15 pounds of refrigerant
The full-charge limit is 15 pounds, with the permanently attached pump-out exception. This does not define a small appliance, which has a separate five-pound factory-sealed definition. Source: 40 CFR 82.156(e).
For disposal of a high-pressure appliance with a full charge of less than 200 pounds, recovery equipment manufactured or imported on or after November 15, 1993 must achieve at least:
Correct answer: A. 0 psig
The Table 1 target is 0 inches Hg vacuum, equivalent to 0 psig at standard atmospheric pressure, for a high-pressure appliance with a full charge below 200 pounds. This applies to disposal as well as opening for major repair; disposal does not change this row to 10 inches Hg vacuum. Source: 40 CFR 82.156(a), Table 1.
For a leaky high-pressure appliance where the required evacuation level is not reasonably attainable, the appliance must:
Correct answer: B. Be recovered under the leaking-component exception to the lowest attainable level, no higher than 0 psig.
Isolate leaking and non-leaking components where possible. Recover non-leaking components to Table 1; recover leaking components to the lowest level attainable without substantially contaminating the refrigerant, no higher than 0 psig. The exception is not automatic permission to stop at 0 psig. Source: 40 CFR 82.156(a)(2).
To identify the refrigerant in an unknown high-pressure appliance, you can:
Correct answer: A. Check the nameplate or use a refrigerant identifier.
Identify an unknown refrigerant by reading the appliance nameplate or by sampling the charge with a refrigerant identifier. Mixing recovered refrigerants of different types contaminates both, so confirming the type before recovery is essential.
At standard sea-level atmospheric pressure of approximately 14.7 psi, how do you convert psig to psia?
Correct answer: B. Add 14.7
Add local atmospheric pressure to gauge pressure. At the stated standard condition, psia = psig + 14.7. Atmospheric pressure varies with altitude and weather, so 14.7 is not universally exact.
In a high-pressure system, the receiver:
Correct answer: A. Stores high-pressure liquid refrigerant.
A receiver stores liquid refrigerant downstream of the condenser. Its permitted storage capacity and pump-down limits depend on the design; do not assume every receiver can hold the entire system charge or always provides subcooled liquid.
Hydrocarbon refrigerants (such as propane) are:
Correct answer: B. Not approved for retrofits in conventional systems
Hydrocarbon refrigerants (propane R-290, isobutane R-600a) are flammable. EPA SNAP approves them only for new equipment specifically designed and certified to handle flammable refrigerants — not as retrofits in existing CFC/HCFC systems where electrical components and seals weren't built for flammables. They are not interchangeable with HFCs.
Hermetic compressor motor windings should never be energized while the system is under a deep vacuum because:
Correct answer: B. Reduced dielectric strength can cause winding burnout.
In a hermetic compressor the refrigerant gas surrounding the motor is what gives the windings their dielectric (insulating) strength. Under deep vacuum that gas is gone, so applied voltage can arc between turns and burn the motor out. The other answers (running too fast, overcharging, neutral on time) are not real consequences of energizing the windings under vacuum.
What must machinery-room refrigerant detection and ventilation be based on?
Correct answer: A. The refrigerant hazards and applicable equipment, code, and standard requirements.
Select and configure detection and ventilation for the actual refrigerant and applicable requirements. An oxygen sensor alone is not a universal substitute for detecting halocarbon refrigerant exposure or flammability hazards.