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EPA 608 Universal study materials
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EPA 608 Universal practice questions

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Question 1Type I - small appliances

Under EPA Section 608, a small appliance is defined as an appliance charged with no more than how much refrigerant?

  1. 5 pounds Correct answer.
  2. 15 pounds
  3. 2 pounds
  4. 50 pounds

Explanation

Type I certification covers small appliances, which EPA defines as appliances containing 5 pounds or less of refrigerant. Appliances with larger charges fall under the Type II or Type III rules.

Question 2Type I - small appliances

A technician finishes servicing a household refrigerator and finds refrigerant left in the service hoses. What is the proper action?

  1. Recover it into a recovery cylinder Correct answer.
  2. Vent it slowly to the outdoors through a hose
  3. Release it into a plastic recovery bag
  4. Discharge it through a filter-drier to the room

Explanation

Section 608 prohibits knowingly venting refrigerant to the atmosphere during service, maintenance, repair, or disposal. Refrigerant trapped in hoses must be recovered or routed back into a cylinder rather than released.

Question 3Type I - small appliances

Recovery equipment that relies on the compressor inside the appliance to move refrigerant out of the system is called:

  1. system-dependent Correct answer.
  2. self-contained
  3. reclaiming
  4. passive

Explanation

System-dependent recovery equipment has no compressor of its own and uses the appliance's compressor and internal pressure to drive refrigerant into the recovery cylinder. Self-contained equipment carries its own compressor.

Question 4Type I - small appliances

A recovery cylinder may be filled to what maximum level?

  1. 80 percent by weight Correct answer.
  2. 85 percent by weight
  3. 100 percent by weight
  4. 90 percent by weight

Explanation

Recovery cylinders must be filled to no more than 80 percent of capacity by weight. The remaining 20 percent provides vapor space so liquid refrigerant can expand as it warms without overpressurizing or rupturing the cylinder.

Question 5Type I - small appliances

Which of the following is classified as a small appliance under EPA regulations?

  1. A household dehumidifier Correct answer.
  2. A centrifugal chiller holding 900 pounds
  3. An industrial freezer holding 60 pounds
  4. A supermarket rack system holding 400 pounds

Explanation

Small appliances include refrigerators, freezers, dehumidifiers, under-the-counter ice makers, vending machines, drinking water coolers, and room air conditioners that contain 5 pounds or less of refrigerant. Equipment with larger charges is regulated under other appliance categories.

Question 6Type I - small appliances

Before cutting into the sealed system of a small appliance, a technician must first:

  1. install a new filter-drier
  2. recover the refrigerant Correct answer.
  3. evacuate the system with a vacuum pump
  4. purge the system with nitrogen

Explanation

Refrigerant must be recovered from the system before any line or joint is opened, because releasing it would violate the venting prohibition. Evacuation and filter-drier replacement happen later, after the repair is complete and the system is closed again.

Question 7Type I - small appliances

How should refrigerant cylinders be stored?

  1. Upright and secured against tipping Correct answer.
  2. In a heated cabinet to maintain pressure
  3. Lying flat on a shelf
  4. In a closed vehicle for security

Explanation

Cylinders should be kept upright and secured so they cannot fall, which keeps liquid away from the valve outlet and protects the valve from damage. They must also be kept away from heat and out of enclosed spaces that can overheat.

Question 8Type I - small appliances

A technician adds refrigerant to a small appliance that has a known leak and no leak-repair obligation under Section 608. What should be done before or during the charge?

  1. The appliance may be charged with any refrigerant on hand
  2. The leak may be ignored because small appliances are unregulated
  3. Refrigerant may be vented until the leak is located
  4. The leak should be located and repaired before charging Correct answer.

Explanation

Even though the leak-rate repair and reporting rules do not apply to small appliances, good practice and the venting prohibition mean the leak should be found and corrected before recharging. Adding refrigerant to a known leak simply repeats the release.

Question 9Type I - small appliances

When recovering refrigerant from a small appliance manufactured after November 15, 1993, the recovery equipment must be capable of removing what percentage of the charge?

  1. 95 percent
  2. 70 percent
  3. 90 percent Correct answer.
  4. 80 percent

Explanation

Recovery equipment used on small appliances manufactured on or after November 15, 1993 must be able to remove 90 percent of the refrigerant charge. Appliances built before that date carry a lower 80 percent requirement.

Question 10Type I - small appliances

A system-dependent recovery device is used on a small appliance whose compressor will not run. What percentage of the charge must be recovered?

  1. 80 percent
  2. 100 percent
  3. 90 percent Correct answer.
  4. 50 percent

Explanation

With system-dependent equipment, recovery from a small appliance must reach 80 percent of the charge when the appliance compressor is operating and 90 percent when it is not.

Question 11Type I - small appliances

The Section 608 leak inspection, repair, and reporting requirements apply to appliances containing how much refrigerant?

  1. More than 15 pounds
  2. Any amount at all
  3. 50 or more pounds Correct answer.
  4. More than 5 pounds

Explanation

Leak-rate calculation, repair, and reporting obligations attach to appliances with a charge of 50 pounds or more. Small appliances fall below that threshold, although venting refrigerant from them remains illegal.

Question 12Type I - small appliances

What is the most accurate way to charge a small appliance with refrigerant?

  1. Watching the sight glass for bubbles
  2. Reading the suction gauge only
  3. Weighing the refrigerant into the system on a scale Correct answer.
  4. Filling until the high-side pressure matches the nameplate

Explanation

Small systems are critically charged, so the charge must be measured by weight with a scale according to the manufacturer's specification. Gauges and sight glasses are indirect indicators that can mislead on equipment with a small charge.

Question 13Type I - small appliances

A recovery cylinder used for small appliance refrigerant must be:

  1. a cylinder rated to 1000 psi and painted gray
  2. a pressure vessel with the relief valve removed
  3. a DOT-approved cylinder with a current test date Correct answer.
  4. a stainless steel tank labeled with the owner's name

Explanation

Refrigerant must be recovered into a DOT-approved recovery cylinder whose hydrostatic test date has not expired. The cylinder must also be in good condition and never filled above 80 percent by weight.

Question 14Type I - small appliances

Why should recovered refrigerant from different appliances never be mixed in one recovery cylinder?

  1. Mixing drives the cylinder pressure below atmospheric
  2. It cannot be identified or reclaimed to specification Correct answer.
  3. Mixed refrigerant will freeze and destroy the recovery machine
  4. Mixing two refrigerants always causes an immediate explosion

Explanation

A mixture of refrigerants cannot be identified or separated, so a reclaimer cannot restore it to specification and it may have to be destroyed. Mixing also contaminates the cylinder and any equipment the refrigerant is later run through.

Question 15Type I - small appliances

Which practice speeds recovery when a system-dependent device is used on a small appliance?

  1. Opening the appliance suction line to the atmosphere
  2. Sealing the appliance inside an insulated box
  3. Warming the recovery cylinder with an open flame
  4. Chilling the recovery cylinder in a cooler Correct answer.

Explanation

Cooling the recovery cylinder lowers its internal pressure, which increases the pressure difference driving refrigerant out of the appliance and into the cylinder. Heating the appliance slightly can also help, but an open flame must never be used.

Question 16Type I - small appliances

A refrigerant identifier is used to:

  1. locate small leaks in the evaporator coil
  2. confirm the refrigerant type and its purity Correct answer.
  3. measure the moisture content of the compressor oil
  4. weigh the total refrigerant charge in the system

Explanation

An identifier analyzes refrigerant vapor to determine which refrigerant is present and whether it is contaminated. This prevents mixing incompatible refrigerants and helps detect counterfeit or contaminated refrigerant before recovery.

Question 17Type I - small appliances

Refrigerant that has been recovered and cleaned of oil, moisture, and other contaminants so it can be reused is called:

  1. virgin refrigerant
  2. recycled refrigerant Correct answer.
  3. azeotropic refrigerant
  4. reclaimed refrigerant

Explanation

Recycling removes contaminants such as oil and moisture from recovered refrigerant so it can be put back into the same system or another system of the same owner. Reclaiming goes further, reprocessing the refrigerant to the purity of new product at a certified facility.

Question 18Type I - small appliances

To calculate how much refrigerant has been recovered into a cylinder, a technician needs the cylinder's:

  1. relief valve setting
  2. internal volume in cubic feet
  3. hydrostatic test pressure
  4. tare weight Correct answer.

Explanation

Tare weight is the weight of the empty cylinder. Subtracting it from the gross weight on the scale gives the weight of refrigerant inside, which is how fill level and recovered amount are determined.

Question 19Type I - small appliances

On a small appliance with no service valves, refrigerant is recovered by:

  1. installing a piercing-type access valve on the process tube Correct answer.
  2. opening the capillary tube and catching refrigerant in a bag
  3. cutting the process tube with a tubing cutter while the system runs
  4. heating the compressor sump until the charge boils off

Explanation

Sealed systems without service ports are accessed with a clamp-on piercing valve installed on the process stub, and refrigerant is recovered through that valve before the system is opened. Cutting lines while a charge is present would release refrigerant.

Question 20Type I - small appliances

A small appliance must have its refrigerant recovered, but its compressor will not run. What should the technician do?

  1. Vent the charge, since the appliance is being scrapped
  2. Bypass the compressor overload to force it to run
  3. Use a self-contained recovery machine Correct answer.
  4. Seal the lines and send the appliance to a landfill

Explanation

System-dependent recovery cannot work when the appliance compressor is inoperative, so a self-contained recovery machine must be used to pull the charge out. Applying power to a failed compressor or venting the charge is never acceptable.

Question 21Type I - small appliances

A household refrigerator is being scrapped. What must happen to its refrigerant?

  1. It may be vented to the atmosphere because the appliance is being destroyed.
  2. Only the compressor oil must be drained; the refrigerant may be released.
  3. It must be recovered before the appliance is dismantled. Correct answer.
  4. It may be vented to the atmosphere if the charge is under one pound.

Explanation

Section 608 requires refrigerant to be recovered from appliances before they are dismantled or discarded, and the venting prohibition applies even to equipment being destroyed. Draining oil does not remove refrigerant from the sealed circuit.

Question 22Type I - small appliances

Recovery and recycling equipment used on small appliances must be:

  1. rebuilt from components listed by the appliance maker
  2. certified to EPA standards by an independent lab Correct answer.
  3. registered with the local fire marshal before each use
  4. inspected annually by a state environmental agency

Explanation

EPA requires recovery and recycling equipment to be certified by an independent testing organization, such as UL, as meeting the recovery efficiency standard for the type of appliance being serviced. Certification applies to equipment designed for small appliances as well as other categories.

Question 23Type I - small appliances

A technician uses a system-dependent recovery device on a small appliance whose compressor runs normally. Recovery is considered complete when:

  1. the recovery cylinder stops gaining weight on the scale
  2. the appliance has been pulled down to a 500-micron vacuum
  3. 80 percent of the charge has been recovered Correct answer.
  4. the suction line feels warm and the low-side gauge reads zero

Explanation

For system-dependent recovery from a small appliance, the required endpoint is 80 percent of the refrigerant charge when the appliance compressor is operating. When the compressor is not operating, 90 percent must be recovered and a self-contained machine is normally needed.

Question 24Type I - small appliances

After a repair has been completed on a small appliance, air and moisture are removed from the system by:

  1. flushing the system with CFC-12 vapor
  2. adding nitrogen and leaving it in the system
  3. opening the suction line to room air
  4. evacuating the system with a vacuum pump Correct answer.

Explanation

Evacuation with a vacuum pump lowers the system pressure so that non-condensables are drawn out and trapped moisture boils off. Refrigerant must never be used to purge or blow out a system, because that practice releases refrigerant to the atmosphere.

Question 25Type I - small appliances

A technician certified only as Type I may legally perform service that involves which of the following?

  1. A centrifugal chiller using R-123
  2. A household refrigerator containing 4 pounds of R-134a Correct answer.
  3. A commercial rooftop unit containing 30 pounds of R-410A
  4. An automobile air-conditioning system using R-134a

Explanation

Type I certification covers small appliances, which are hermetically sealed, factory-charged appliances containing 5 pounds or less of refrigerant. A household refrigerator with 4 pounds falls within that category. Rooftop units and chillers require Type II or Type III certification, and motor vehicle air conditioning is covered under Section 609.

Question 26Type I - small appliances

What must be done with refrigerant removed from a small appliance that is being repaired?

  1. It may be vented only if the appliance is being scrapped.
  2. It may be vented if the charge is less than 5 pounds.
  3. It may be discharged into a sealed container of water.
  4. It must be recovered and not released to the atmosphere. Correct answer.

Explanation

Section 608 prohibits venting refrigerant to the atmosphere, so refrigerant removed during service must be recovered. The 5-pound small-appliance charge size does not create an exception that allows venting. Releasing refrigerant into water or venting it because the appliance is being scrapped is also prohibited.

Question 27Type I - small appliances

Why should a recovery cylinder never be filled completely with liquid refrigerant?

  1. Refrigerant will change color when compressed.
  2. The cylinder becomes too heavy to move safely.
  3. Liquid refrigerant expands with temperature and can overpressurize the cylinder. Correct answer.
  4. The recovery machine cannot pump into a full cylinder.

Explanation

Recovery cylinders must be filled by weight and left with vapor space because liquid refrigerant expands as it warms. Overfilling can cause hydrostatic pressure high enough to rupture the cylinder. Standard practice limits filling to about 80 percent of the cylinder capacity.

Question 28Type I - small appliances

What is the standard color marking for a DOT refrigerant recovery cylinder?

  1. Gray body with a yellow top Correct answer.
  2. White body with a blue stripe
  3. Solid red with a black top
  4. Solid green with a white band

Explanation

DOT recovery cylinders are commonly gray with a yellow top so they can be identified as recovery containers. The color marking helps prevent recovered refrigerant from being confused with virgin refrigerant cylinders.

Question 29Type I - small appliances

Which method is appropriate for locating a refrigerant leak on a small appliance?

  1. Smelling the refrigerant at the service port
  2. Using an electronic leak detector Correct answer.
  3. Pressurizing with oxygen and watching for bubbles
  4. Holding an open flame near the tubing

Explanation

Electronic leak detectors and soap-bubble solutions are safe and effective ways to locate refrigerant leaks. Open flames and oxygen must never be used because they create fire and contamination hazards. Refrigerant odor is not a reliable or safe leak-detection method.

Question 30Type I - small appliances

Which gas should be used to pressurize a small appliance for leak testing?

  1. Acetylene
  2. Compressed air from a shop compressor
  3. Dry nitrogen Correct answer.
  4. Oxygen

Explanation

Dry nitrogen is inert and does not introduce moisture into the refrigeration system, making it the preferred leak-testing gas. Compressed air can contain moisture and oil, while oxygen and acetylene create serious fire or explosion hazards.

Question 31Type I - small appliances

Why is a vacuum pump used instead of the appliance's own compressor to evacuate a small appliance?

  1. The vacuum pump automatically recharges the system.
  2. The appliance compressor cannot run without a refrigerant charge.
  3. The appliance compressor is not designed to pull a deep vacuum. Correct answer.
  4. A vacuum pump heats the refrigerant for reuse.

Explanation

A refrigeration compressor is designed to pump refrigerant, not to evacuate a system to a deep vacuum. Using it as a vacuum pump can overheat it and damage the compressor. A dedicated vacuum pump is required to remove air and moisture properly.

Question 32Type I - small appliances

Which instrument is used to measure the vacuum level during evacuation of a small appliance?

  1. A refrigerant scale
  2. A micron gauge Correct answer.
  3. An electronic leak detector
  4. A manifold gauge set high-side gauge

Explanation

A micron gauge measures deep vacuum accurately, which is necessary to confirm that air and moisture have been removed. Standard manifold gauges are not precise enough at the low absolute pressures used during evacuation.

Question 33Type I - small appliances

What distinguishes a self-contained recovery machine from a system-dependent recovery device?

  1. It works only on appliances with no service valves.
  2. It uses the appliance's compressor to move refrigerant.
  3. It has its own compressor to move refrigerant. Correct answer.
  4. It does not require a recovery cylinder.

Explanation

A self-contained, or system-independent, recovery machine has its own compressor and can recover refrigerant even if the appliance compressor is not operating. A system-dependent device relies on the appliance's compressor to move refrigerant.

Question 34Type I - small appliances

Which process produces refrigerant that has been analyzed and certified to meet AHRI Standard 700?

  1. Reclaiming Correct answer.
  2. Recycling
  3. Evacuating
  4. Recovering

Explanation

Reclaiming requires chemical analysis and processing to restore refrigerant to AHRI Standard 700 purity. Recycling is a simpler cleaning process and does not include the laboratory certification required for reclaimed refrigerant.

Question 35Type I - small appliances

Which heat source is acceptable for warming a small appliance during refrigerant recovery?

  1. An open torch flame
  2. A heat gun set to maximum
  3. Warm water Correct answer.
  4. A space heater placed directly against the cabinet

Explanation

Warm water or another gentle heat source can be used to help move refrigerant out of a small appliance without creating a fire hazard. Open flames and excessive heat can damage the appliance or overpressurize the system.

Question 36Type I - small appliances

Which refrigerant state is generally recovered faster from a small appliance?

  1. Liquid refrigerant Correct answer.
  2. Superheated vapor
  3. A mixture of air and vapor
  4. Refrigerant vapor at low pressure

Explanation

Liquid refrigerant contains much more mass per unit volume than vapor, so recovering it as a liquid is generally faster. Vapor recovery is slower because the recovery machine must compress a low-density gas.

Question 37Type I - small appliances

When charging a small appliance with a zeotropic refrigerant blend, the refrigerant should be withdrawn from the cylinder as:

  1. A superheated gas
  2. A vapor
  3. A liquid Correct answer.
  4. A mixture of liquid and vapor

Explanation

Zeotropic blends fractionate, meaning their components can separate when vapor is withdrawn. Charging as a liquid helps maintain the correct refrigerant composition.

Question 38Type I - small appliances

What is the purpose of low-loss fittings on recovery hoses?

  1. They allow the cylinder to be filled to 100 percent.
  2. They increase the recovery rate by heating the refrigerant.
  3. They filter moisture from the refrigerant.
  4. They reduce refrigerant release when hoses are disconnected. Correct answer.

Explanation

Low-loss fittings are designed to minimize refrigerant released when hoses are connected or disconnected. They do not heat refrigerant, filter moisture, or permit overfilling of the recovery cylinder.

Question 39Type I - small appliances

How should used compressor oil removed from a small appliance be handled?

  1. Spread on the ground outdoors to evaporate
  2. Poured into a floor drain with plenty of water
  3. Mixed with the recovered refrigerant in the recovery cylinder
  4. Collected and disposed of according to local and federal regulations Correct answer.

Explanation

Used compressor oil is a regulated waste and must be collected and disposed of properly. It must not be poured down drains, spread outdoors, or mixed with recovered refrigerant.

Question 40Type I - small appliances

After evacuating a small appliance, the technician isolates the vacuum pump and the micron gauge rises quickly from 500 to 2000 microns. What does this most likely indicate?

  1. The vacuum pump oil is new.
  2. A leak or moisture is present in the system. Correct answer.
  3. The system is fully dehydrated and ready to charge.
  4. The micron gauge is out of calibration.

Explanation

A rapid rise in pressure after isolation indicates that air is entering through a leak or that moisture is vaporizing in the system. A fully dehydrated system should hold a low vacuum without a fast rise. The technician should find and correct the cause before charging.

Question 41Type I - small appliances

A small refrigerator has a heavy frost pattern on the suction line at the evaporator outlet. Which condition is most likely?

  1. Low refrigerant charge or a restriction Correct answer.
  2. Too much compressor oil
  3. Overcharge of refrigerant
  4. A disconnected defrost heater

Explanation

A low charge or a restriction lowers suction pressure and temperature, which can cause heavy frost or ice to form on the suction line. An overcharge would typically raise pressures rather than create this low-pressure frost pattern.

Question 42Type I - small appliances

Following a compressor burnout in a small appliance, which test helps determine whether acid remains in the system?

  1. An acid test of the compressor oil Correct answer.
  2. A soap-bubble leak check
  3. A nitrogen pressure test
  4. A micron gauge reading

Explanation

Compressor burnout can produce acids in the system, and an acid test of the oil helps determine whether contamination remains. Pressure, vacuum, and leak tests do not measure acid levels.

Question 43Type I - small appliances

Why should a refrigerant cylinder never be heated with an open flame?

  1. The pressure can rise enough to rupture the cylinder. Correct answer.
  2. The cylinder label will become unreadable.
  3. The flame will change the refrigerant's boiling point.
  4. The refrigerant will leak through the valve stem.

Explanation

Heating a refrigerant cylinder raises its internal pressure, and an open flame can cause dangerous overpressurization or rupture. Warm water is the acceptable gentle heat source when heating is needed.

Question 44Type I - small appliances

What information should be marked on a cylinder containing recovered refrigerant?

  1. The type of refrigerant and the date of recovery Correct answer.
  2. The EPA certification exam score
  3. The technician's home address
  4. The date the appliance was manufactured

Explanation

Recovered refrigerant cylinders should be labeled with the refrigerant type and recovery date so the contents are not misidentified or mixed. Proper labeling helps ensure the refrigerant is handled and reused or reclaimed correctly.

Question 45Type I - small appliances

Under EPA Section 608, who may purchase refrigerant for servicing small appliances?

  1. A properly certified technician Correct answer.
  2. Only the appliance owner
  3. Any hardware store employee
  4. Any person with a valid driver's license

Explanation

Section 608 requires technicians who service refrigeration equipment to be certified, and refrigerant sales to service technicians are restricted to certified persons. A driver's license, appliance ownership, or retail employment does not satisfy the certification requirement.

Question 46Type I - small appliances

Why should a technician ventilate the work area when recovering refrigerant from a small appliance?

  1. To keep the vacuum pump oil cool
  2. To avoid inhaling refrigerant vapors Correct answer.
  3. To prevent the recovery cylinder from rusting
  4. To increase the recovery speed

Explanation

Refrigerant vapors can displace oxygen and cause dizziness or other health effects, so the work area should be well ventilated. Ventilation does not speed recovery, prevent cylinder rust, or cool vacuum pump oil.

Question 47Type I - small appliances

Why should liquid refrigerant be prevented from entering the compressor of a small appliance during system-dependent recovery?

  1. Liquid refrigerant cannot be recovered.
  2. Liquid refrigerant will freeze the recovery cylinder.
  3. Liquid refrigerant turns into air.
  4. Liquid can damage the compressor valves. Correct answer.

Explanation

Liquid refrigerant entering a running compressor can cause slugging, which may bend or break compressor valves. System-dependent recovery should control the rate so refrigerant returns to the compressor as vapor.

Question 48Type I - small appliances

The oil in a vacuum pump turns milky after evacuating a small appliance. What does this indicate?

  1. The pump is operating at peak efficiency.
  2. Moisture has contaminated the pump oil. Correct answer.
  3. The micron gauge is reading inaccurately.
  4. The system has a refrigerant overcharge.

Explanation

Milky vacuum-pump oil usually indicates that the pump has absorbed moisture from the system. The oil should be changed, and the evacuation may need to be repeated to remove remaining moisture.

Question 49Type I - small appliances

A technician recovers refrigerant from a small appliance and cannot verify its purity. What is the proper disposition of the refrigerant?

  1. Install it in another appliance of the same type.
  2. Mix it with new refrigerant to dilute impurities.
  3. Vent it slowly outdoors.
  4. Send it to a reclaiming facility for analysis. Correct answer.

Explanation

Refrigerant of unknown purity must be sent to a reclaiming facility for analysis and processing before reuse. It cannot be installed in another appliance, vented, or diluted with new refrigerant.

Question 50Type I - small appliances

A technician is recovering refrigerant from several small appliances into an empty DOT-approved recovery cylinder. Which filling practice is required?

  1. Stop filling when the cylinder reaches 80 percent of its capacity by weight Correct answer.
  2. Stop filling when the cylinder reaches 90 percent of its capacity by weight
  3. Stop filling when the cylinder's gross weight equals its tare weight
  4. Fill the cylinder completely, since recovery cylinders are built for liquid-full storage

Explanation

Recovery cylinders must be limited to 80 percent of their capacity by weight so that headspace remains for liquid expansion as the cylinder warms. Overfilling can hydrostatically stress the cylinder and cause it to rupture or relieve refrigerant through the safety device.