Part 3 HVAC Core

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What range is displayed on a high pressure gauge on a service manifold? A. 500 micronsto 0 psi B. 0 to 200 psi C. 0 to 800 psi D. 250 psi to 750 psi

0 to 800 psi

Before making a major repair, technicians must evacuate an appliance or component containing more than 200 pounds of R-410A to which of the following levels? A. 0 psig B. 25 mm Hg absolute c. 10 inches of Hg vacuum D. 15 inches of Hg vacuum

10 inches of Hg vacuum

Approximately how much refrigerant vapor is left in an average 350-ton R-123 chiller at O pig once all the R-123 liquid has been removed? A. Trace amount B. 50 pounds C. 75 pounds D. 100 pounds

100 pounds

A rupture disc on a recovery vessel for low-pressure refrigerants relieves at; A. 5 psig. B. 10 psig. C. 15 psig.. D. 20 psig.

15 psig

What evacuation level must technicians recover refrigerant to before disposing a low-pressure appllance? A. 0 psig B. 15 inches of Hg vacuum C. 25 inches of Hg vacuum D. 25 mm of Hg absolute

25 mm of Hg absolute

How long must a technician evacuating refrigerant from appliances with a full charge of more than 5 pounds and less than 50 pounds that are being disposed of keep records of the event? A. 1 year B. 3 vears C. 5 years D. 10 years

3 years

R-123 at a pressure of 18.1 inches Hg vacuum has a saturation temperature of: A. 28°F B. 32°F C. 36°F D. 40°F

40°F

What is the approximate pressure of a storage cylinder of recovered R-134a that does not contain anv non-condensable impurities and is stored in a room where the temperature is 80° F? A. 37 psig B. 87 psig c. 157 psig D. 207 psig

87 psig

To avoid freezing the water contained in a water-cooled heat exchanger of an R-134a refrigeration system during charging, the system should he initially charged with R-134a vapor to a pressure of approximately: A. 0 psig. B. 10 psig. c. 30 psig, D. 90 psig.

90 psig

Which of the following CANNOT be used as a reason to extend the appliance leak repair deadlines? A Requirements of federal, state or local regulations make the repair within 30 days impossible. B. The appliance is located in an area that is subject to radiological contamination. C. Necessary repair parts are unavallable. D. A certified service technician is not available.

A certified service technician is not available.

All appllances must be equipped with a service aperture or process stub which is used when adding or removing refrigerant from the appliance. What is typically used on small appliances? A. A straight piece of tubing that is entered using a plercing access valve. B. Aline located 15 inches below the compressor C, A valve installed at the factory which has a 1/4 Inch diameter and machine threads. D. A service aperture is not present because small appllances are exempt from this requirement,

A straight piece of tubing that is entered using a plercing access valve.

Recovered refrigerant may contain which of the following impurities? A. Ammonia, carbon dioxide, and methyl chloride B. Sodium chloride, potassium nitrate, and silicone oil C, Sulphur dioxide and methane D. Acids, moisture, and oil

Acids, moisture, and oil

Which types of refrigerant can only be sold to persons who have successfully passed the EPA's Section 608 certification exam? A. Only ozone-depleting substances used in comfort cooling. B. Only non-ozone-depletine substances used in commercial refrigeration. C. Only substitute refrigerants used in Industrial process refrigaration. D. All refrigerants that are not exempt from the venting prohibition.

All refrigerants that are not exempt from the venting prohibition

Who must certify recovery equipment used during maintenance, service or repair of small appliances that use CFCs, HCFCs, and HFCs? A. An ASHRAE-approved laboratory. B. Recovery equipment for small appliances does not require approval. C, An AHRI740 standards laboratory. D. An EPA-approved laboratory.

An EPA-approved laboratory

Which of the following does NOT meet the criteria for Type lappllance certification? A. An MVAG-like system that holds three pounds of R-12. B. A water cooler that holds 13 ounces of R-22. C. A food freezer that holds 22 ounces of R-134a D. A dehumidifier that holds seven ounces of R-410A.

An MVAG-like system that holds three pounds of R-12.

What type of appliances are technicians certified to charge and open after passing the Type evamination? A. Appliances containing 5 pounds or less of refrigerant that have been hermetically sealed and charged at the factory. B. Split systems containing 5 pounds or less of refrigerant that have been hermetically sealed and charged at the factory. Appliances containing 5 pounds or less of refrigerant that have an open drive compressor and have been charged at the factory. D. Motor vehicle air-conditioning equipment.

Appliances containing 5 pounds or less of refrigerant that have been hermetically sealed and charged at the factory.

Which of the following is not a reason to recover refrigerants? A. Provide supplies for service after the refrigerant has been phased out. B. Prevent venting to the atmosphere. C. Prevent stratospheric ozone depletion. D. Avoid violating the warranty on equipment.

Avoid violating the warranty on equipment

Generally, chillers belong to which EPA leak repair category? A. Commercial refrigeration B. Industrial process refrigeration C. Comfort cooling D. Ice making refrigeration

Comfort cooling

Which leak repair category does the EPA define as air-conditioning appliances used to provide cooling in order to control heat and/or humidity in occupied facilities including, but not limited to, residential, office, and commercial buildings? A. Commercial refrigeration B. Industrial process refrigeration C. Comfort cooling D. Ice making refrigeration

Comfort cooling

What precaution should be taken prior to recovering refrigerant from a chiller suspected of having tube leaks? A. Drain the water sides of the evaporator and condenser. B. Run the circulating pumps. C. Be certain the purge unit is operating. D. Open the condenser vents.

Drain the water sides of the evaporator and condenser.

You have to leak-checka unit which has lost a complete charge. Which gases) would cause the LEAST damage to the environment? A. Dry nitrogen and R-22 B. Compressed air and R-12 C. Dry nitrogen D. Dry nitrogen and R-134a

Dry nitrogen

You are changing out the compressor of a system cöntaining 40 pounds'of R-404A, Mi addition to isolating the compressor, which of the following procedures should you follöw? A. Simply remove the compressor and cap the ends. B. Evacuate the isolated section of the system to atmospheric pressure, then remove the compressor. C. Evacuate the isolated section of the system to 0 psig and if system pressure does not rise after a few minutes, remove the compressor. D. Evacuate the isolated section of the system to 5 inches of Vacuum and when the system's pressure rises out of the vacuum, remove the compressor.

Evacuate the isolated section of the system to 0 psig and if system pressure does not rise after a few minutes, remove the compressor.

When can appliances containing refrigerants be recovered to atmospheric pressure? A. For major repairs such as replacing the compressor, condenser, or evaporator. B. The repair is followed by an evacuation of the appliance to the enviranment. C. Leaks in the appliance make recovery to the prescribed level unattainable. D. The appliance is being disposed of and recycled.

For major repairs such as replacing the compressor, condenser, or evaporator.

Which of the following indicates air in a low-pressure system? A. High head pressure. B. High liquid level. C. Low head pressure. D. Low suction pressure.

High head pressure

What will non-condensables in a refrigeration system result in? A. Lower suction pressure B. Higher suction pressure C. Lower discharge pressure D. Higher discharge pressure

Higher discharge pressure

Pressure relief valves can only be installed; A. In series. B. in parallel. C. vertically. D. horizontally.

In Parallel

Pressure relief valves must not be installed; A. in series. B. in parallel. C. vertically. D. horizontally.

In series

Where would you place a leak detector probe to check gas leaks into the water box with water A. At the rupture disc seal. B. Around the vent valve. C. Around a test plug. D. In the drain valve opening.

In the drain valve opening.

What effect will low ambient temperatures have on recovery? A. shortened recoverv time. B. Increase the recovery time. C Minimize emissions. D. Require frequent drier changes.

Increase the recovery time

How does the global warming potential of R-410A compare to carbon dioxide? A. It is lower. B. They are equal. C, It is hundreds of times greater. D.' It is thousands of times greater.

It is thousands of times greater

Which of the following statements is true of recycling and recovery equipment? A. It must be tested by an AHARl-approved third party. B. It must be equipped with low-loss ball valves and flare fittings. C. It must be able to handle more than one refrigerant. D. It must be labeled as certified to meet EPA's requirements,

It must be labeled as certified to meet EPA's requirements

Why should the oil be removed from a low-pressure system at 130°F? A. 130°F is the normal operating temperature for oil in a low-pressure system. B. Less refrigerant will be contained in the oil at the higher temperature. C. Warmer oil has a lower viscosity and flows more easily. D. It shows that the heater is working.

Less refrigerant will be contained in the oil at the higher temperature.

After system servicing, and recharging, why is refrigerant vaporre-intfoduced to the chiller before refrigerant liquid? A. Vapor charging increases pressure slowly, preventing failure of the ruptare disk B.. Vapor charging is faster than liquid charging, C. Liquid charging is more difficult to control than vapor charging. D. Liquid charged into a deep vacuum will evaporate and may lower the temperature freezing water in the heat exchanger tube bundle.

Liquid charged into a deep vacuum will evaporate and may lower the temperature freezing water in the heat exchanger tube bundle.

What is the primary water source for a water cooled recovery unlt's condensing coil? A. Chilled water from the evaporator B. Condenser water C. Local municipal water supply D. De ionized water

Local municipal water supply

What Is the state of the refrigerant entering the compressor of a refrigeration system? A. Low pressure liquid B. Low pressure vapor C. High pressure liquid D. High pressure vapor

Low pressure vapor

Under what conditions may you use a disposable cylinder to recover refrigerant? A.. When the system contains the same refrigerant as the cylinder, B. When the system contains less than 10 lbs, of refrigerant. C. When disposing of the refrigerant. D. Never

Never

During evacuation with large amounts of moisture it may be necessary to increase pressure to counteract freezing with gas such as; A. R-410A. B. R-22. C. Air. D. Nitrogen.

Nitrogen

Permanent safety markings are NOT required on which of the following areas on household refrigerators using HC refrigerants? A. On or near any evaporators and near any exposed refrigerant tubing. B. Near the machine compartment, C. On the inside of the refrigerator door. D. On the exterior of the refrigerator.

On the inside of the refrigerator door.

Which type of lubricants are HO refrigerants are miscible in? A. AB lubricants B. POE lubricants C. Mineral oils D. All refrigerant lubricants

POE lubricants

What gases can CFC and HFC refrigerants decompose into at high temperatures, (e.g., open flames, glowing metal surfaces, etc.)? A. Hydrazire gas B. Phosgene gas C. Heliumgas D. Tetraethyl gas

Phosgene gas

Which of the following are included in EPA's definition of a "small appliance?" A. Products fully manufactured, charged and hermetically sealed in a factory. B. Products having 15 pounds or less of refigerant. c.Products with compressors under ½ horsepower. D. Fully charged components ready for installation in a split system.

Products fully manufactured, charged, and hermetically sealed in a factory

What must be done before shipping any used refrigerant in a cylinder? A. Properly label the refrigerant container. B. Fill the cylinder to capacity. C. Check that the recipient is Section 608 certified to recycle refrigerant. D. Pressure check the refrigerant,

Properly label the refrigerant container

Which of the following statements about recycling and recovery equipment is FALSE? A. It must be tested by an EPA-approved third party B. Purchases of such equipment must be reported to the EPA C. It must be equipped with low-loss fittings D. Equipment designed to recover flammable refrigerant must meet specific UL safety standard

Purchases of such equipment must be reported to the EPA

Which of the following refrigerants contains chlorine? A. R-22 B. R-134a C. R-410A D. R-1234Vf

R-22

Which of the following refrigerants has the lowest global warming potential? A. R-134a B. R-407C C R-410A D. R-600

R-600

Which ofthe following is an approved substitute refrigerant for new household refrigerators, freezers, and combination refrigeration/freezers? A. R-600a B. R-1234yf C. R-1234zd D. R-170

R-600a

For what refrigerant is an equipment room refrigerant detector NOT required under ASHRAE Standard 15 provided the mechanical ventilation system In the machinery is run continuously? A. R-134a B. R-4-04A C. R-4-10A D. R-717

R-717

What is the term for removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way? A. Recycling B. Recovering C Reclaiming D. Restoring

Recovering

Recovery devices for use with small appliances containing CFCs, HFCs, and HFCs must meet which of the following requirements? A. Recovering 90% of the refrigerant when the compressor is operating or achieving a 4-inch vacuum under the conditions of AHRI 740 B. Recovering 80% of the refrigerant when the compressor is operating c. Recovering 95% of the refrigerant when the compressor is operating or achieving a 10-inch vacuum under the conditions of AHRI 740 D. Recovering 75% of the refrigerant when the compressor is operating

Recovering 90% of the refrigerant when the compressor is operating or achieving a 4-inch vacuum under the conditions of AHRI 740

What is the center port on a three port manifold used for? A. Obtaining gauge readings. B. Pumping air into system. C. By-pass from low to high side. D. Recovery, evacuation, and charging.

Recovery, evacuation and charging

When using nitrogen in repairing a sealed refrigeration system, what should the nitrogen tank always be equipped with? A. Regulator B. Float sensor C. Red top D. Hand valve

Regulator

In which of the following scenarios can refrigerant be vented? A. Releasing R-410A from household refrigerators. B. Releasing mixed refrigerant from a recovery cylinder. C. Releasing Isobutane from a household freezer, D. Releasing R-22 from appliances with a charge less than 5 pounds.

Releasing isobutane from a household freezer

What is the primary purpose of a purge unit on a low-pressure chiller? A. Remove refrigerant from the system. B. Condense air out of the system. C. Condense water out of the system. D. Remove non-condensables from the system.

Remove non-condensables from the system

Your recovery/recycling machine has R-22 refrigerant in it. You now have to recover refrigerant from an R-410A unit. What must be done before recovery? A. Change the recovery cylinder on the recovery machine. B. Change the expansion valve on the recovery machine. C. Change the filter and expansion valve on the recovery machine. D. Remove the R-22 from the recovery unit and change the filter.

Remove the R-22 from the recovery unit and change the filter

Which of the following is NOT required to mothball an appliance (thereby extending the leakrepair deadline)? A Shut down the appliance temporarily B. Remove the appliance and store it in a warehouse at the facility C. Recover the refrigerant from the isolated section or component D. Recover refrigerant from the appliance to at least, atmospheric pressure

Remove the appliance and store it in a warehouse at the facility

Which of the following repairs would always be considered "major" under EPA's regulations? A. Replacement of an evaporator coll. B. Replacement of a filter-drier. C. Replacement of a Schrader valve core. D. Replacement of a condenser fan motor

Replacement of a Schrader valve core.

Which of the following actions would always be considered "major" under EPA's regulations? A. Replacement of an evaporator coil B. Replacement of a filter-drier C. Replacement of a switch D. Replacement of a purge unit

Replacement of an evaporator coil

Which ofthe following always falls under the EPA definition for "major maintenance, service, or repair?" A. Replacing an oil filter B. Replacing an expansion valve C. Replacing a compressor D. Replacing an accumulator

Replacing a compressor

When working with an appliance containing HFCs or HFCs, which of the following does NOT require a person to be a Section 608 certified technician? A. Removing refrigerant. B. Rewiring an external electric circuit. C. Replacing a component. D. Performing any activity that violates the refrigerant circuit.

Rewiring an external electric circuit

Leak testing a low-pressure refrigeration system with nitrogen in excess of 10 psig could cause which of the following to fail? A. Condenser tubes B. Purge unit shells C. Evaporator tubes D. Rupture disc

Rupture disc

What does ozone depletion potential (or 'ODP') measure? A. The ability of a substance to cause global warming, B. The ability of a substance to destroy ozone in the stratosphere. C. A rating of health hazards caused by ozone depletion. D. The length of time a refrigerant stays in the atmosphere.

The ability of a substance to destroy ozone in the stratosphere

What should be done before transferring refrigerant to an empty cylinder? A. The refrigerant should be chilled. B. The refrigerant should be mixed, C. The cvlinder should be heated. D. The cylinder should be evacuated.

The cylinder should be evacuated

When installing any type of access fitting onte a sealed system;... A. The fitting should be leak tested before proceeding with recovery. B. it is not necessary to leak test an access fitting. c. the fitting need not be leak tested until the total repair is completed. D. the system must he pressurized with dry nitrogen before leak testing can be attempted,

The fitting should be leak tested before proceeding with recovery

Why could a recycling or recovery machine that uses a hermettc compressor overheat when drawing deep vacuums? A. It runs faster than other equipment with oil less compressors. B. The motor relies on the flow of refrigerant through the compressor for cooling. C.It has a higher compression ratto limit than other equipment. D. The oils used in hermetic compressors are a lower viscosity than the oils used in other equipment.

The motor relies on the flow of refrigerant through the compressor for cooling.

Who is responsible for keeping records of all leak inspections and any completed leak repair verification tests? A. The original installing technician's employers B. Only the technician that has actually performed each inspection or verification test C. The owner and/or operator of the equipment D. The EPA leak rate assessment division

The owner and/or operator of the equipment

What should be on and what should be off during vapor removal from a Jow-pressure refrigeration system? A. The system water pumps should be on and the recovery comprassor should be off. B. The system water pumps and recovery compressor should be on, and the recovery condenser water should be off, C. The system water pumps, recovery compressor, and recovery condenser water should all be on. D. The system water pumps should be off, and the recovery compressor should be on.

The system water pumps, recovery compressor, and recovery condenser water should all be on.

How do the global warming potentials of isobutane (R-600a), propane (R-290), and R-441A compare to the GWPs of HFC-134a, R-404A, and R-410A? A. They are significantly higher B. They are significantly lower C. They are approximately equal D: Theyare Just slightly higher

They are significantly lower

What characteristic of HFC refrigerants make them damaging to the environment? A. They ate toxic to plants and animals at low doses. B. They contain chlorine which damages the ozone layer. C. They have a high Ozone Depletion Potential (ODP). D. They can have very high global warming potentials.

They can have very high global warming potentials.

What characteristics) of CFCs and HFCs make them more likely to reach the stratosphere than most other compounds containing chlorine? A. They do not dissolve in water or easily break down in the atmosphere. B. They are lighter than other chlorine compounds, making it easier for them to reach the stratosphere when released, C. They are stored under pressure, causing them to jet upward when released. D, Thev are attracted to ultraviolet radiation.

They do not dissolve in water or easily break down in the atmosphere.

Which of the following is a reason to heat a system during dehydration? A. To prevent oxidation. B. To increase oil viscosity. C, To decrease dehydration time. D. To increase dehydration time,

To decrease dehydration time

Why should low and high side access valves be installed when recovering refrigerant from a household refrigerator? A. To improve speed of recovery. B. To prevent non-condensables contamination. C. To protect the recovery machine, D. To prevent, oil migration.

To improve speed of recovery

Why do EPA regulations require appllances to have a service aperture or process stub? A. To make it easier to recover refrigerant, B. To check for open motor windings. C. To vent non-condensibles. D. To dehydrate the system oil.

To make it easier to recover refrigerant

Why do gauge set hoses used for field service work have self-sealing connectors or hand valves? A. To minimize the chance of an explosion during refrigerant recovery. B. To prevent vapor lock during vaportransfer to recovery cylinder. C. To minimize refrigerant release when hoses are connected and disconnected. D. To prevent vapor lock during liquid transfer to recovery cylinder.

To minimize refrigerant release when hoses are connected and disconnected.

Why must water be circulated through a chiller during refrigerant evacuation? A. To speed up the recovery process. B. To prevent loss of refrigerant to the atmosphere, C. To prevent freezing of water in the appliance. D. To maintain constant refrigerant pressure in the appliance.

To prevent freezing of water in the appliance

Where does the purge unit on a centrifugal system take its suction? A. Top of the condenser B. Compressor oil sump C. Top of the evaporator D. Suction elbow

Top of the condenser

A major system repair is being performed on an R-22 appliance. What CANNOT be done to recharge the appliance? A. Add R-22 after the repair is completed. B. Retrofit the unit to R-407C, C. Use recovered or recycled R-22 from the same owner. D. Top off the unlt with R-410A.

Top off the unit with R-410A

What may be done to speed the recovery process and ensure that all CFC, HFC, or HFC refrigerant has been removed from a frost-free refrigerator? A. Cool the compressor to force liquid out of the high side. B. Heat the recovery cylinder to vaporize liquid refrigerant. C. Turn on the defrost heater to increase the refrigerant's tamperature and vaporize any liquid. D. Pack ice around the evaporator to ensure maximum liquid is available.

Turn on the defrost heater to increase the refrigerant's tamperature and vaporize any liquid.

When pressurizing a refrigeration system with nitrogen what rule should you always follow? A. Charge nitrogen as a liquid. B. Use a pressure regulator with a pressure relief valve on the nitrogen cylinder. C.Pressurize to above 1000 psig. D. Never use nitrogen inside the system.

Use a pressure regulator with a pressure relief valve on the nitrogen cylinder

Which of the following releases of a refrigerant is illegal? A. Venting a refrigerant that EPA has determined doas not pose a threat to the environment. B. Venting refrigerant from a recovery machine or recovery cylinder. C. Releasing refrigerant while connecting or removing low loss service hoses. D. Small "de minimis" releases while making a good faith effort to recover refrigerant.

Venting refrigerant from a recovery machine or recovery cylinder

Which of the following are recommended safe work practices when recovering refrigerants? A. Wear safety eyewear and buty!-fined gloves when connecting/disconnecting hoses. B. Wear a respirator when working with any refrigerant. C. Wear cotton gloves when working with any compressed gas. D. Ventilation is only necessary if oil, appearing as a white cloud or fog, is emitted during the recovery procedure.

Wear safety eyewear and buty!-fined gloves when connecting/disconnecting hoses.

When should an appliance NOT be evacuated all the way to the prescribed level? A. When preforming a major repair followed by a minor repair. B. When the repair is followed by an evacuation of the appliance to the environment. C. When leaks In the appliance make evacuation to the prescribed level unattainable. D. When the appliance is being disposed of at a later date.

When leaks In the appliance make evacuation to the prescribed level unattainable.

When does ASHRAE Standard 25-2013 require that each machinery room activate an alarm and mechanical-ventilation? A. When the TLV-TWA (Threshold Limit Value - Time Weighted Average) is exceeded. B. When the UTL (Upper Threshold Limit) is exceeded. C.. When the COP (Coefficient of Performance) drops 5% of the original value. D. When the EEL (Emergency Exposure Limlt) is exceeded by 10%.

When the TLV-TWA (Threshold Limit Value - Time Weighted Average) is exceeded.

When is it against EPA regulations to use system-dependent recovery equipment? A. When the compressor of the appliance is operational. B. When the ambient temperature is over 105°F. C. When the appliance contains over 15 pounds of refrigerant. D. When the appliance is leaking.

When the appliance contains over 15 pounds of refrigerant.

Which condition requires accessing both the high and low side of the system for refrigerant recovery when using the system-dependent (passive) recovery process? A. When there is a leak in the sustem.. B. When the compressor operates normally. C. When the compressor only runs at half speed. D. When the compressor does not run

When the compressor does not run

When could a reciprocating compressor be damaged If energized? A. When the dscharge service valve is closed. B. When the suction service valve is open. C. When the discharge service valve is open. D. When the demand for cooling is at a steady state,

When the dscharge service valve is closed.

Which of the following additions of refrigerant, when added to an appllance that contains 50 or more pounds of an ozone-depleting refrigerant, triggers the requirement to calculate the leak rate? A. Following a retrofit. B. During the installation of a new appliance. C. Using a qualified seasonal variance, D. When topping off the system.

When topping off the system

When is it essential to take measures to hslp release trapped CFC, HCFC, or HFC reifigerant from the compressor oil during refrigerant recovery? A. When using self-contained recovery devices. B. When using system-dependent active recovery devices. C. When using passive recovery devices on small appliances with non-operating compressors. D. When the refrigerant system has a low side leals.

When using passive recovery devices on small appliances with non-operating compressors.

When R-410A is recovered from an appliance, It; A. can be mixed with elther R-32 or R-125a during the recovery process, since R-410A is a mixture of those two refrigerants. B. can be mixed with R-134a but not R-22 during the recovery process. C. need not be recovered since R-410A is not one of the refrigerants covered by the Clean Alr Act. D. should be recovered into a recovery vessel that is clearly marked to ensure that mixing of refrigerants does not occur,

can be mixed with R-134a but not R-22 during the recovery process.

EPA Section 608 rules require capture of 80% of the HFCs and HFCs from a small appliance sealed system with a non-operating compressor if technicians are using; A. a system-dependent (passive) process, B. a selfcontained (active) process. C. either a passive or an active recovery process. D. neither recovery process.

either a passive or an active recovery process.

When using a self-contained recovery device on a CFC, HCFC, or HFC system with an operating compressor, technicians must; A. recover the refrigerant to 5 inches of mercury vacuum. B. recover 80% of the nameplate charge, c. recover the refrigerant to both 4 inches of mercury vacuum and 80% of the nameplate charge. D. either recover the refrigerant to 4 inches of mercury vacuum or 90% of the nameplate charge.

either recover the refrigerant to 4 inches of mercury vacuum or 90% of the nameplate charge

When recovering CFC, HFC, or HFC refrigerant into a non-pressurized container from a household refrigerator with an inoperative compressor it is; A. helpful to heat and strile the compressor with a rubber mallet B. only necessary to recover as much refrigerant as will naturally flow out of the system. C: not necessary to recover since the refrigerant is probably contaminated. D. necessary to chase refrigerant from the oil with pressurized dry nitrogen.

helpful to heat and strile the compressor with a rubber mallet

On low-pressure chillers, moisture most frequently enters the refrigerant system through; A. air leaks in the rupture disc assembly. B. tube leals in the evaporator. C. leaks from areas with gaskets or fittings. D. leaks from the charging service valve.

leaks from areas with gaskets or fittings.

Refrigarant has been recovered from an air-conditioning system and held in a refillable cylinder, in order to replace the condenser coil, The refrigerant; A may be charged back Into the system, B. may be sold as is to another equipment owner. c must be reclaimed, D. must be destroyed.

must be destroyed.

A standard vacuum pump designed specilically for evacuation and dehydration can; A. be used alone as a self-contained (active) recovery device. B. never be used as a recovery device in combination with a pressurized container. C. be used alone as a substitute for any recovery device. D. be used alone as a system-dependent (passive) recovery device.

never be used as a recovery device in combination with a pressurized container

When servicing a small appliance found to be leaking It is; A mandatory to repair the leak within 30 days. B. mandatory to repair the leak only when the annualized leak mte exceeds 15% of the total charge. C. not mandatory to repair the leak but it is recommended to do so whenever possible. D. mandatory to recover all remaining refrigerant and dispose of the appliance.

not mandatory to repair the leak but it is recommended to do so whenever possible.

The system dependent (passive) recovery process; A. neverneeds the use of a pump or heat to recover refrigerant. B. must use a pressure relief device to protect the technician and equipment. C. recovers refrigerant in a non-pressurized container. D. can only be performed on a system with an operating compressor.

recovers refrigerant in a non-pressurized container.

The sale of CFC, HCFC, HFC, and HFO refrigerants to service or install refrigeration and air conditioning equipment is; A. banned from use unless you have a recovery machine. B. limited by law to HVAC Contractors and / or Mechanical Engineers. C allowed only if there is proof of need. D. restricted to techniclans who are EPA certified in refrigerant recovery.

restricted to techniclans who are EPA certified in refrigerant recovery.


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