EPA 608 Type III

Identify the pressure corresponding to 32 degrees F for R-123: ________. a) 23 inches of Hg vacuum b) 20 inches of Hg vacuum c) 17 inches of Hg vacuum d) 11 inches of Hg vacuum

A hydrostatic tube test kit is used to: _________. a) blow all water from the tubes b) remove any water from the machine c) vent refrigerant d) determine if a tube leaks

Excessive running of a purge system on a low pressure chiller generally indicates that the: ___________. a) air sensors are faulty b) ambient temperature is too high c) efficiency of the purge unit is too low d) system is leaking

When recovering vapor from a low pressure refrigeration system: __________. a) water pumps should all be on, and the recovery compressor should be off b) system water pumps should be on, the recovery compressor should be on, and the recovery condenser water should be off c) the systems water pumps, the recovery compressor, and the recovery condenser water should all be on d) system water pumps should be off, and the recovery compressor should be on

ASHRAE Standard 15 - 1994 requires equipment room refrigerant sensors for what safety group classifications? a) A1 b) B2 c) A2 d) All refrigerant safety group classifications.

If you are using a recovery machine manufactured BEFORE November 15, 1993, you must evacuate any low-pressure appliance to _______ before making a major repair. a) 0 psig b) 15 inches of Hg vacuum c) 25 inches of Hg vacuum d) 25mm of Hg absolute

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

The primary water source for a recovery unit condensing coil is: _________. a) chilled water b) condenser water c) local municipal water supply d) de-ionized water

Which of the following repairs that 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

According to the EPA, there is approximately ________ of refrigerant vapor left in an average 350 ton R-11 chiller at 0 psig pressure once all the R-11 liquid has been removed. a) None. b) 10 pounds. c) 20 pounds. d) 100 pounds.

A centrifugal chiller's rupture disk is connected to the chiller's: ________. a) condenser b) evaporator c) liquid line d) economizer

When charging a chiller, refrigerant vapor is introduced into the system before charging with liquid. That is because: ___________. a) vapor charging increases pressure slowly, preventing failure of the rupture disc 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 cause the refrigerant to boil and lower temperatures enough to freeze the water in the tubes

To determine how much vapor to charge into an evacuated chiller, you should charge with vapor until: __________. a) the system pressure corresponds to a refrigerant saturation temperature of 36 degrees F b) the recovery unit liquid level drops c) you have charged with vapor for 15 minutes d) the recovery unit pressure drops

When there is excessive moisture collecting in the purge unit of a low pressure refrigeration system, this indicates that: _________. a) the system was charged with contaminated refrigerant b) the condenser or chiller barrel tubes are leaking c) the purge unit is not operating properly d) the purge unit needs adjustment

During chiller evacuation, water is circulated to: _________. a) speed up the recovery process b) prevent loss of refrigerant to the atmosphere c) prevent freezing of the water d) maintain constant refrigerant pressure

A system does not have to be evacuated all the way to the required level when: __________. a) the repair is major b) the repair is followed by an evacuation of the appliance to the environment c) the appliance is being disposed of d) leaks in the appliance make evacuation to the prescribed level unattainable

What is meant by the term "high efficiency purge unit"? a) Those purge units which discharge a high percentage of refrigerant with the air which they remove. b) Those purge units which discharge a low percentage of refrigerant with the air which they remove. c) Those purge units which draw very little electrical power. d) None of the above.

The maximum test pressure for leak testing a low pressure centrifugal is: ________. a) 0 psig b) 10 psig c) 25 psig d) 50 psig

When recharging a refrigeration system with R-11, what vapor pressure is necessary in the shells before charging with liquid? a) 21.1 inches of Hg vacuum b) 19.7 inches of Hg vacuum c) 18.1 inches of Hg vacuum d) 16.9 inches of Hg vacuum

During the evacuation of a system containing large amounts of moisture, you can prevent freezing of this moisture by increasing the pressure with ______ gas. a) nitrogen b) R-22 c) air d) oxygen

Both CFC-11 and HCFC-123 chillers require purge units because: ___________. a) the purge units remove moisture b) the system operates below atmospheric pressure c) purge units remove refrigerant from the oil sump d) purge units remove CFCs from the chiller

If you are going to remove oil from a low pressure system, you should heat the oil because: __________. a) you can warm your hands on the container 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

Refrigerant is added to a centrifugal machine through the: _________. a) float valve b) compressor service valve c) condenser charging valve d) evaporator charging valve

If you leak test a low pressure chiller with nitrogen in excess of 10 psig you could cause the _______ to fail. a) condenser tubes b) purge unit shells c) evaporator tubes d) rupture disc

To remove ice from sight glasses or viewing glasses, use: _________. a) R-11 refrigerant b) an alcohol spray c) water d) a screw driver of flat file

What steps may be taken to prevent air accumulation into an idle low pressure refrigeration system? a) Leave the purge unit on-line at all times. b) System pressure should be maintained slightly above atmospheric. c) Open the air vents on the condenser. d) Intermittently operate the system with no load.

If you suspect a leak in the water box of a chiller, you should place the leak detector probe _________, and sniff for refrigerants. a) at the rupture disc b) through the vent valve c) through a test plug d) through a drain valve

What precaution should be taken prior to recovering refrigerant from a chiller suspected of having tube leaks? a) Draining the water sides of the evaporator and the condenser. b) Run the circulating pumps. c) Be certain the purge unit is operating. d) Open the condenser vent.

A typical setting for the high pressure cut-out control on a recovery unit used for evacuating the refrigerant from a low pressure chiller is: _______. a) 2 psig b) 5 psig c) 10 psig d) 15 psig

The lowest access point on a low pressure centrifugal air-conditioning unit is the: _________. a) evaporator charging valve b) the condenser service valve c) the compressor cooler jacket d) the purge unit exhaust port

The discharge from a rupture disc should be piped _______ for venting. a) outdoors b) inside the machinery room c) to the evaporator d) to the duct system

The typical design burst pressure for a rupture disk on a low pressure centrifugal air conditioning system is set at: _______. a) 7 psig b) 10 psig c) 15 psig d) 28 psig

After reaching the required recovery vacuum on a chiller, you should: _____________. a) immediately disconnect the recycling or recovery equipment and open the system for service b) wait for at least a few minutes to se if the system pressure rises, indicating there is still refrigerant in liquid form or in the oil c) immediately break the vacuum with nitrogen and open the system for service d) wait for at least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in liquid form or in the oil

After recovering the liquid refrigerant you must: ___________. a) recover the vapor refrigerant b) pressurize the system with nitrogen c) remove the oil from the system d) solvent-flush the entire system

Which statement is NOT true of recycling and recovery equipment manufactured AFTER November 15, 1993? a) It must be tested by an EPA-approved third party. b) It must meet vacuum standards more stringent than those met by equipment manufactured before November 15, 1993. c) It must be equipped with low-loss fittings. d) It must be able to handle more than one refrigerant.

The purge unit takes its suction from the: _________. a) top of the condenser b) compressor oil sump c) top of the evaporator d) suction elbow

On low pressure chillers, moisture typically enters the refrigerant system through: _________. a) air leaks in the rupture disc assembly b) tube leaks c) air leaks from areas with gaskets or fittings d) air leaks from the charging valve

When charging an R-410A water chiller, you must first charge with vapor to a pressure of at least _______, before switching to liquid charging. a) 20 psig b) 120 psig c) 220 psig d) 320 psig

On a low-pressure chiller with an open-type compressor, the ________ is very susceptible to leaks. a) chiller tubes b) shaft seal c) charging connections d) shaft bearings

The PRIMARY purpose of a purge unit on a CFC-11 chiller is to: ___________. a) remove CFCs from the system b) condense air out of the system c) condense water out of the system d) remove non-condensables from the system

Which safety precautions should be adhered to for low pressure systems? a) Do not siphon refrigerant by mouth. b) Avoid spilling liquid refrigerant on the skin. c) Use gloves and safety goggles when working with liquid refrigerant. d) All of the above.

According to ASHRAE Guideline 3-1996, if the pressure in a system rises from 1 mm Hg to a level above _______ during a standing vacuum test, the system should be checked for leaks. a) 1.5 mmHg b) 2.0 mm Hg c) 2.5 mm Hg d) 3.0 mm Hg

Refrigerant recovery typically starts with ________ because it is faster. a) vapor recovery b) liquid recovery c) combined vapor and liquid recovery d) oil separation

Refrigerant-11 at 14.7 PSIA will boil at about: _________. a) 60.3 degrees F b) 74.5 degrees F c) 79.7 degrees F d) 80.2 degrees F

Pressure relief valve must never be: __________. a) installed in series b) installed in parallel c) installed vertically d) installed horizontally

Charging refrigerant liquid into a refrigeration system when it is under a 29" HG vacuum can cause the: ___________. a) liquid to absorb excess moisture b) purge unit to operate c) system water to freeze d) refrigerant liquid to freeze

ASHRAE Standard 15 - 1994 requires the use of room sensors and alarms to detect: __________. a) refrigerant leaks b) high levels of ozone c) refrigerant contamination d) excessive oxygen levels

Commercial and industrial process refrigeration systems must be repaired when the leak rate exceeds _____ of the charge per year. a) 5% b) 15% c) 20% d) 35%

Under EPA's regulations, __________ is used to pressurize a low-pressure chiller for the purpose of opening the system for a non-major repair. a) adding nitrogen b) warming the refrigerant c) adding compressed air d) adding carbon dioxide

A charged low pressure refrigeration system can be efficiently leak checked by: ___________. a) adding compressed air, since it will be removed from the system by the purging unit b) operating the purge system c) adding HCFC-22 d) raising system pressure by heating with circulated hot water or heating blankets

The existence of air in a low pressure system causes: ____________. a) low head pressure b) low suction pressure c) high head pressure d) high liquid level

An oil sample should be taken when: ____________. a) a new filter-drier has been installed b) there has been a compressor burnout c) the unit is not cooling properly d) recycled refrigerant has been added to the unit

According to ASHRAE Standard 34, what is the safety classification of R-123? a) A1 b) A2 c) B1 d) B2

Refrigerant-11 at a pressure of 17" Hg vacuum has a saturation temperature of: _______. a) 30 degrees F b) 35 degrees F c) 40 degrees F d) 44 degrees F

Which repair WOULD NOT fall under the EPA definition for "MAJOR MAINTENANCE, SERVICE, OR REPAIR"? a) Replacing an oil filter. b) Replacing the compressor. c) Re-tubing a condenser. d) Replacing a fin and tube forced air evaporator coil.

Which action listed below is the proper method to reduce refrigerant loss from a purge unit on a CFC-11 chiller? a) Leak test and repair the chiller. b) Seal the purge-unit discharge. c) Pipe purge-unit back into the low size. d) Pipe purge-unit into recovery unit.

EPA regulations require that any appliance containing more than 50 pounds of refrigerant (except for commercial and industrial process refrigeration) must be repaired when the leak rate exceeds _____ of the charge per year. a) 5% b) 15% c) 20% d) 35%

ASHRAE Standard 15 - 1994 requires that each machinery room must activate an alarm and mechanical ventilation before refrigerant concentrations exceed: _________. a) the Eel (Emergency Exposure Limit) b) the TLV-TWA (Threshold Limit Value - Time Weighted Average) c) the UTL (Upper Threshold Limit) d) the COP (Coefficient of Performance)

When evacuating a system, the use of too large a vacuum pump can cause: _________. a) trapped water to freeze b) trapped oil to freeze c) trapped refrigerant to freeze d) valves to freeze

Where does refrigerant go after it leaves the purge unit of a low pressure centrifugal system? a) [To] the evaporator. b) [To] the condenser. c) [To] the compressor intercooler. d) [To] the recovery service vessel.

If you are using a recovery machine manufactured AFTER November 15, 1993, you must evacuate any low-pressure appliance to ________ before making a major repair. a) 0 psig b) 15 inches of Hg vacuum b) 25 inches of Hg vacuum d) 25 mm of Hg absolute

A chiller's rupture disk is connected to the system's ___________. 1) low pressure side 2) high pressure side 3) never used

When leak testing a low pressure centrifugal, what is the maximum test pressure? 1) 0.1 psig 2) 10 psig 3) 10 inches of Mercury 4) 14.7 psia 5) 50 psig

What is the EPA's estimate for how much refrigerant vapor is left in an average 350 ton R-11 chiller at 0 psig pressure, once all the R-11 liquid has been removed? 1) 1.5 lbs 2) 3.0 lbs 3) 10 lbs 4) 20 lbs 5) 100 lbs 6) 1000 lbs

How would you SAFELY reduce refrigerant loss from a purge-unit on a low pressure unit? 1) Leak test and repair the chiller. 2) Seal the purge-unit discharge. 3) Plumb the purge-unit discharge back into the low side. 4) Plumb the purge-unit into the recovery unit.

When recharging a refrigeration system with R-11, why is refrigerant vapor added first to raise the system pressure? 1) To prevent freezing of the water in the heat exchanger (water box). 2) To reduce the stress on the rupture disk. 3) To speed recharging. 4) To prevent condensation.

If you suspected a low pressure system leak at the water box, where would you place your leak detector? 1) At the rupture disk. 2) At the recovery port. 3) At the vent valve. 4) At the service port. 5) At the water box drain port.

A hydrostatic tube test kit will ________. 1) determine if a tube leaks 2) determine if there is water in the system 3) remove water from a machine 4) vent water

Leak testing at 20 psig would definitely cause which of the following to fail? 1) Condenser 2) Compressor 3) Purge-unit 4) Evaporator 5) Rupture disk

EPA regulations require that all appliances containing more than 50 pounds of refrigerant (except for commercial and industrial process refrigeration) be repaired when the leak rate exceeds _________ of the charge per year. 1) 10% 2) 15% 3) 20% 4) 25% 5) 18% 6) 35%

Leaking commercial and industrial process refrigeration must be repaired when the leak rate exceeds _________ of the charge per year. 1) 10% 2) 15% 3) 20% 4) 25% 5) 18% 6) 35%

When evacuating the refrigerant from a low pressure chiller, using a push-pull method, the recovery unit's high pressure cut-out should be set for ___________. 1) 2 psia 2) 2 psig 3) 5 psia 4) 5 psig 5) 10 psia 6) 10 psig 7) 15 psia 8) 15 psig

For low pressure systems, refrigerant removal starts with __________. 1) vapor removal 2) liquid removal 3) vapor & liquid removal 4) oil separation

According to ASHRAE Guideline 3-1996, if the pressure in a system rises from 1 mm Hg to above __________ during a standard vacuum test, the system should be checked for leaks. 1) 1.5 mm Hg 2) 2.2 mm HG 3) 2.5 mm Hg 4) 0.5 mm Hg

Oil should be heated before removing so that _________. 1) you can warm your hands on the oil container 2) less refrigerant will be contained in the oil 3) the warmer oil will flow more easily 4) acid levels are reduced

A rupture disk on a recovery vessel for low pressure refrigerants relieves at _________. 1) 5 psig 2) 5 psia 3) 10 psig 4) 10 psia 5) 15 psig 6) 15 psia

During vapor removal from a low-pressure refrigeration system, the water pump is on to prevent ___________. 1) corrosion 2) freezing 3) boiling 4) none of the above

When a heater is used on a refrigerant storage cylinder, it increases the rate of _________ transfer to the chiller. 1) dirt 2) refrigerant 3) oil 4) none of the above

If you are using a water-cooled recovery unit, __________ is the primary water source for the recovery unit's condensing coil. 1) chilled water 2) condenser water 3) local municipal water supply 4) de-ionized water 5) bottled water

When recharging a refrigeration system with R-11, _________ vapor pressure is necessary in the shells before charging with liquid. 1) 20" Hg, Vacuum 2) 17" Hg, Vacuum 3) 10 psig 4) 27 psia

After reaching the required recovery vacuum on an appliance, you should _________. 1) immediately disconnect the recycling or recovery equipment and open the system for service 2) wait for at least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in liquid form or in the oil 3) immediately break the vacuum with nitrogen and open the system for service 4) immediately pressurize the system with nitrogen and perform a leak check

Which repair is a "major" repair under EPA's regulations? 1) Replacement of an evaporator coil. 2) Replacement of a filter-drier greater than 8 cubic inches, 3) Replacement of a run or start capacitor. 4) Replacement of a fan or water pump motor.

The EPA believes that the most effective method of leak checking low pressure refrigeration machines is with __________. 1) dry nitrogen 2) HCFC-22 3) hot water 4) the purge system

Low pressure appliances can be pressurized to atmospheric pressure when _________. 1) the recovery system is broken 2) the CFC is more than 10 years old 3) leaks in the appliance make evacuation to the prescribed level unattainable 4) the appliance is being disposed of

On low pressure units, the EPA believes that moisture most frequently enters the refrigerant system through ___________. 1) air leaks at the rupture disk 2) tube leaks 3) air leaks from gasketed areas and/or fittings 4) air leaks from the charging valve

All EPA recovery units must __________. 1) recover more than one refrigerant 2) be compatible with Ester and mineral oils 3) operate on 60 cycle U.S. power 4) have a minimum 30 day warrantee 5) none of the above 6) both 1 and 2

The PRIMARY purpose of a purge-unit on a CFC-11 chiller is to ________. 1) purge CFCs from the system 2) condense water from the system 3) condense air out of the system 4) clean the refrigerant 5) remove non-condensables from the system 6) purge solid particles from the system

On a low pressure centrifugal system, the purge-unit suction is connected to the _________. 1) condenser 2) evaporator 3) oil sump 4) suction side compressor inlet

How would you determine when enough vapor has entered the refrigeration system before charging with refrigerant liquid? 1) When the saturation temperature is above the freezing point of water. 2) When the pressure relief valve vents slightly. 3) When the recovery unit shuts off. 4) After 2.5 minutes.

Refrigerant is added to a centrifugal machine through the ________. 1) float valve 2) compressor service valve 3) condenser charging valve 4) evaporator charging valve 5) queen valve

What refrigerant(s) require an equipment room oxygen deprivation sensor (as per ASHRAE Standard 15)? 1) R-12 2) R-134a 3) R-11 4) none of the above 5) all of the above 6) only 2 and 3

What refrigerant(s) require an equipment room refrigeration sensor (as per ASHRAE Standard 15)? 1) R-12 2) R-134a 3) R-123 4) none of the above 5) all of the above 6) only 2 and 3

Under what code group of ASHRAE Standard 34 does R-123 fall? 1) A1 2) A2 3) B1 4) G2 5) B2 6) B123

On a low pressure system, a centrifugal chiller's purge condensing unit _________. 1) returns refrigerant to the unit 2) removes air and non-condensables from the system 3) takes its suction from the top of the condenser 4) only 1 and 3 5) none of the above 6) all of the above

What is the saturation pressure of R-11 at 70 degrees F? 1) 2.8 inches of mercury 2) 2.8 mm of mercury 3) 2.8 inches of water 4) 2.8 psia 5) 2.8 psig

R-11 is a _________ refrigerant. 1) CFC 2) HCFC 3) HFC