EPA 608 Type II, Type III:
Under what code group of ASHRAE Standard 34 does R-123 fall?
B1
When dismantling an appliance on site, the technician must;
Ensure that recovery occurs
There are no exceptions to the required evacuation levels established by EPA.
False
Type III certification applies to both high and low pressure chillers?
False
Air entering the refrigerant in a low pressure chiller is always a concern because;
Low pressure chillers can operate at pressures bellow atmospheric.
Low pressure chillers use purge units because;
Low pressure chillers operate bellow atmospheric pressure.
___of equipment with charges of 50 pounds or more must keep records of refrigerant added during service and maintenance.
Owners
At all times a system should be protected by a;
Pressure limiting device
Water should be circulated through the chiller during recovery because it will -
Prevent freeze up
The current accepted alternative refrigerant for R-11 is;
R-123
When using nitrogen with a pressure over 10 PSIG, Which unit could fail?
Rupture disk
R-410A is different from other ASHRAE 400 series non-azeotropic blends because: _______. a) R-410A behaves as a near azeotropic refrigerant, and can be topped off b) R-410A is a HCFC c) R-410A uses mineral oil d) all of the above
a) R-410A behaves as a near azeotropic refrigerant, and can be topped off
Which repair 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 schraeder valve core. d) Replacement of a condenser fan motor.
a) Replacement of an evaporator coil.
Use _________ to remove ice from a sight glass. a) an alcohol spray b) water c) R-11 refrigerant d) a screw driver or flat file
a) an alcohol spray
The refrigerant pressure inside an R-12 unit which is at room temperature (72 degrees F) and not operating is: _________. a) approximately 74 psig b) approximately 154 psig c) approximately 214 psig d) approximately 304 psig
a) approximately 74 psig
Prior to replacing the condenser coil in a high pressure system, the refrigerant was recovered and stored in a refillable cylinder. The refrigerant: __________. a) can probably be charged back into the system b) should probably be replaced with R-410A c) must be reclaimed d) must be destroyed
a) can probably be charged back into the system
Never use oxygen or compressed air to leak-check hardware because R-410A can: _________. a) explode when mixed with air or oxygen b) fractionate when mixed with oxygen c) condense when exposed to oxygen d) none of the above
a) explode when mixed with air or oxygen
Pressure relief valve must not be: ______. a) installed in series b) installed in parallel c) installed vertically d) installed horizontally
a) installed in series
The recovery of refrigerant from a system as a vapor only will minimize the loss of: _____. a) oil b) water c) refrigerant d) all of the above
a) oil
The recovery rate can be increased by: ________. a) packing the recovery vessel in ice b) heating the recovery vessel c) using a smaller recovery vessel d) using a standard vacuum pump
a) packing the recovery vessel in ice
Every air conditioning or refrigerating system should be protected by a: _________. a) pressure relief device b) properly located stop valve c) low pressure control d) refrigerator receiver
a) pressure relief device
In a refrigeration system with a TXV (or other type of throttling device), the component directly following the condenser is the: _______. a) receiver b) metering device c) accumulator d) evaporator
a) receiver
A reciprocating compressor should not be energized [when]: _________. a) the discharge service valve is closed b) the suction service valve is open c) the discharge service valve is open d) there is a demand for cooling
a) the discharge service valve is closed
The evaporation temperature of R-134A at 0 psig is: ____. a) -21 degrees F b) -15 degrees F c) - 5 degrees F d) -1 degree F
b) -15 degrees F
When charging an R-410A system that uses a water-cooled condenser, 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
b) 120 psig
The EPA regulations require that any appliances 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) 25% d) 35%
b) 15%
The evaporation temperature of R-410A at 100 psig is about: ______. a) 0 degrees F b) 30 degrees F c) 90 degrees F d) 120 degrees F
b) 30 degrees F
When using recovery and recycling equipment manufactured BEFORE November 15, 1993 technicians must evacuate a unit that has a normal charge of 10 pounds of CFC-500 to _______ before disposing of the system. a) 0 psig b) 4 inches of Hg vacuum c) 10 inches of Hg vacuum d) 15 inches of Hg vacuum
b) 4 inches of Hg vacuum
When a refrigerant trace gas becomes absolutely necessary, which of the available refrigerants should be used to identify a leak? a) CFC-12 b) HCFC-22 c) HFC-407C d) HFC-410A
b) HCFC-22
Which component is NOT part of the low side of the system? a) Evaporator b) Receiver c) Suction line d) Accumulator
b) Receiver
When leak testing a low pressure chiller, the maximum test pressure should be;
10 PSIG
The rupture disk on a chiller is generally set for;
15 PSIG
If a chiller providing comfort cooling has a leak rate of__or more, it must be repaired.
15%
EPA's required evacuation level for a low pressure appliance using equipment manufactured after November 15, 1993 is;
25 mm Hg absolute
EPA's required evacuation level for a low pressure appliance using equipment manufactured before November 15, 1993 is;
25" Hg
What does 25 mm Hg absolute equal?
29" Hg vacuum
When charging a low pressure chiller, refrigerant should be introduced as a vapor to rise saturation temperature above;
32 F
A halide torch should always be used in a well-ventilated area because;
A. Flames and refrigerants can create poisonous gases. B. The pressure of poisonous gasses can displaced necessary oxygen. C. The technician is in close proximity to the torch. D. All of the above.
R-134a is a Group___refrigerant; R-123 is a Group___refrigerant.
A1, B1
One of the standards for machinery room safety is;
ASHRAE 15
Refrigerants;
Are Heaver than air
Your recovery/recycling machine has R-502 refrigerant in it. You now have to recover refrigerant from a unit with R-22. What must be done before the R-22 refrigerant can be recovered/recycled? a) nothing, as long as the recovery machine is not full b) change the expansion valve on the recovery machine c) change the filter and expansion valve on the recovery machine d) recover as much of the R-502 from the recovery unit as possible, change filter, and evacuate
d) recover as much of the R-502 from the recovery unit as possible, change filter, and evacuate
A compressor heater is used to: __________. a) prevent refrigerant vaporization b) remove entrained water c) prevent acid pitting d) reduce the amount of refrigerant in the lubricating oil
d) reduce the amount of refrigerant in the lubricating oil
System-dependent recovery equipment CANNOT be used when: ___________. a) the appliance is leaking b) the compressor of the appliance is operational c) the ambient temperature is over 115 degrees F d) the appliance contains over 15 pounds of refrigerant
d) the appliance contains over 15 pounds of refrigerant
Before transferring refrigerant to an empty cylinder: _____________. a) the refrigerant should be chilled b) the refrigerant should be mixed c) the cylinder should be heated d) the cylinder should be evacuated to avoid mixing air with the recovered refrigerant
d) the cylinder should be evacuated to avoid mixing air with the recovered refrigerant
When inspecting a system for leaks, you should look for: ________. a) frost on the pipes b) puddles of liquid refrigerant c) particles from the drier core d) traces of oil
d) traces of oil
Moisture is removed from a system by: _________. a) purging the condenser b) draining the oil separator c) reducing water flow to the condenser d) using a filter drier
d) using a filter drier
When using recovery or recycling equipment that was manufactured AFTER November 15, 1993: you must evacuate a system containing MORE than 200 pounds of CFC-12 to ________ before making a major repair. a) 0 psig b) 4 inches of Hg vacuum c) 10 inches of Hg vacuum d) 15 inches of Hg vacuum
d) 15 inches of Hg vacuum
The EPA regulations require that leaking commercial or industrial process refrigeration equipment must be repaired when the leak rate exceeds _____ of the charge per year. a) 5% b) 15% c) 25% d) 35%
d) 35%
R-410A requires a high-pressure manifold gauge and hose set. They must have a: _________. a) 2000 psig burst pressure and 400 psig working pressure b) 2000 psig burst pressure and 800 psig working pressure c) 4000 psig burst pressure and 400 psig working pressure d) 4000 psig burst pressure and 800 psig working pressure
d) 4000 psig burst pressure and 800 psig working pressure
Before using a recovery unit to remove a charge, what steps should be taken? a) Check service valve. b) Check the oil level in the recovery unit. c) Evacuate recovery unit and recovery tank. d) All of the above.
d) All of the above.
Recovered refrigerant may contain which of the following? a) Acids b) Moisture. c) Oils. d) All of the above.
d) All of the above.
Your recovery/recycling machine has R-22 refrigerant in it. You now have to recover refrigerant from a unit with R-410A. What must be done before your recovery unit can be used to recover R-410A? a) The recovery unit must be EPA certified for use with R-410A. b) The recovery tank must be designed for the pressure of R-410A. c) The filter and lubricant in the recovery unit must be changed, and the recovery unit evacuated. d) All of the above.
d) All of the above.
Which statement is NOT true about 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 have an oil separator.
d) It must have an oil separator.
For what refrigerant(s) is equipment room refrigerant monitor required under ASHRAE Standard 15? a) R-12 b) R-134a c) R-11 d) R-123
d) R-123
Dry nitrogen should be used to break the first vacuum when dehydrating by the double evacuation method. However, it: ________. a) often contains moisture b) is expensive c) is toxic d) can be dangerous if not used with a pressure regulator
d) can be dangerous if not used with a pressure regulator
A routine maintenance task which must be performed on refrigerant recycling machines is to: __________. a) check compressor seals b) change electrical fuses c) replace moisture sight glass d) change filter and compressor oil (if any)
d) change filter and compressor oil (if any)
After refrigerant liquid has been recovered from a system, any remaining vapor is: _______. a) purged to the atmosphere b) isolated in the system c) pumped into the system receiver d) condensed by the recovery system
d) condensed by the recovery system
Refrigerant should be removed from the condenser outlet if the: ________. a) condenser is on the roof b) compressor is inoperative c) the evaporator has a leak d) condenser is below the receiver
d) condenser is below the receiver
When a unit is opened for servicing, the _______ should always be replaced. a) thermostat b) metering device c) crankcase heater d) filter-drier
d) filter-drier
Noncondensables in a system cause a: _________. a) lower suction pressure b) higher suction pressure c) lower discharge pressure d) higher discharge pressure
d) higher discharge pressure
The method to charge a system that has a normal charge of 80 pounds is to charge with: ________. a) vapor through the suction line service valve b) liquid through the discharge service valve c) liquid through the suction service valve d) liquid through the liquid-line service valve
d) liquid through the liquid-line service valve
The primary water source for cooling the condenser of a water-cooled recovery unit is: _________. a) de-ionized water b) chilled water c) condenser water d) local municipal water supply
d) local municipal water supply
A deep vacuum is usually measured in: _______. a) psig b) psia c) inches of Hg d) microns
d) microns
Manifold gauge set hoses should have self-sealing connectors or hand valves to: _________. a) minimize the chance of an explosion during use b) prevent venting during recycling c) prevent a vapor lock during rapid liquid transfer d) minimize the release of refrigerant when the hoses are connected and disconnected
d) minimize the release of refrigerant when the hoses are connected and disconnected
During the evacuation of the system that contains large amounts of moisture it may be necessary to increase pressure in the system with ______, to counteract the freezing of the moisture. a) hydrogen b) oxygen c) air d) nitrogen
d) nitrogen
Heat pumps that use R-134A should be leak checked with: _______. a) CFCs b) HCFCs c) compressed dry air d) pressurized nitrogen
d) pressurized nitrogen
After installation of a field-piped R-410A split heat pump, the unit should first be: a) evacuated b) pressurized with R-22 then leak checked c) pressurized with R-410A then leak checked d) pressurized with nitrogen then leak checked
d) pressurized with nitrogen then leak checked
While R-410A is a high-pressure refrigerant, it can be stored in the back of your service van as long as: ____________. a) the temperature inside the vehicle does not exceed 125 degrees F. This is the same guidance given for R-22 and other common refrigerants b) the temperature inside the vehicle does not exceed 125 degrees F, but R-22 can be stored in vehicles with temperatures exceeding 125 degrees F c) the temperature inside the vehicle does not exceed 1555 degrees F. This is the same guidance given for R-22 and other common refrigerants d) the temperature inside the vehicle does not exceed 155 degrees F, but R-22 can be stored in vehicles with temperatures exceeding 155 degrees F
a) the temperature inside the vehicle does not exceed 125 degrees F. This is the same guidance given for R-22 and other common refrigerants
Soap bubble testing is used: _________. a) to pinpoint refrigerant leaks b) only with CFCs and HCFCs c) to detect water leaks d) to see if the condenser or evaporator is excessively dirty
a) to pinpoint refrigerant leaks
When under a deep vacuum, the motor winding of a hermetic refrigeration compressor: ________. a) will be damaged if energized b) must be kept warm to operate properly c) will be protected by its insulation if the compressor is started d) will overheat only if the crankcase heater is energized
a) will be damaged if energized
To change the compressor on a system containing R-410A, you must isolate the compressor then: _____________. a) simply remove the compressor b) evacuate the isolated section of the system to atmospheric pressure and hold. If system pressure does not rise, remove the compressor c) evacuate the isolated section of the system to 10 inches of vacuum and hold. If system pressure does not rise, remove the compressor. d) evacuate the isolated section of the system to 15 inches of vacuum and hold. If system pressure does not rise, remove the compressor.
b) evacuate the isolated section of the system to atmospheric pressure and hold. If system pressure does not rise, remove the compressor
The proper charging method for blended (non-azeotropic) refrigerants (400 Series) is to remove the charge from the cylinder as a: _____. a) vapor b) liquid c) superheated vapor d) subcooled liquid
b) liquid
When a new system has been assembled, the first thing to do is: _________. a) evacuate the system b) pressurize the system with an inert gas and leak check c) pressurize the system with refrigerant to be used in the system d) introduce an initial charge of refrigerant and start the compressor
b) pressurize the system with an inert gas and leak check
On refrigeration units that use an open compressor, the: _________ is most likely to leak if the unit is not used for several months. a) suction service valve b) rotating shaft seal c) oil drain plug d) discharge service valve
b) rotating shaft seal
An oil sample should be taken when: _________. a) a new filter drier has been installed b) the compressor has burned out c) the unit is not cooling properly d) recycled refrigerant has been added to the unit
b) the compressor has burned out
A Recovery machine that uses a hermetic compressor will overheat when drawing a deep vacuum because: ___________. a) it runs faster than other equipment b) the motor needs the flow of refrigerant through the compressor to provide motor cooling c) the oils used in hermetic compressors burn at lower temperatures d) it has a higher compression ratio limit than other equipment
b) the motor needs the flow of refrigerant through the compressor to provide motor cooling
When charging an R-12 refrigeration system that uses a water-cooled condenser, you must first charge with vapor to a pressure of at least ______, before switching to liquid charging. a) 0 psig b) 20 psig c) 35 psig d) 100 psig
c) 35 psig
R-410A requires certified recovery and recycling machines rated for at least: ________. a) 240 psig b) 300 psig c) 400 psig d) 500 psig
c) 400 psig
R-410A requires recovery tanks rated for at least: ______. a) 240 psig b) 300 psig c) 400 psig d) 500 psig
c) 400 psig
The vacuum pump used to evacuate a system should be capable of pulling a vacuum of: ________. a) 10 mm Hg b) 20 mm Hg c) 500 microns d) 1000 microns
c) 500 microns
You are going to service an older residential split system air conditioner. You would expect to find the system charged with which refrigerant? a) R-11 b) R-12 c) R-22 d) R-502
c) R-22
You are going to service a newer residential split system air conditioner. You would expect to find the system charged with which refrigerant? a) R-11 b) R-12 c) R-410A d) R-502
c) R-410A
In a refrigeration system, the component directly following the evaporator is the: _______. a) receiver b) metering device c) accumulator d) condenser
c) accumulator
The refrigerant pressure inside an R-410A unit which is at room temperature (72 degrees F) and not operating is: _________. a) approximately 74 psig b) approximately 110 psig c) approximately 210 psig d) approximately 310 psig
c) approximately 210 psig
When evacuating a system, the use of a large vacuum pump could: ________. a) cause trapped oil to freeze b) cause trapped refrigerant c) cause trapped water to freeze d) causes the valves to freeze
c) cause trapped water to freeze
Oil foaming usually occurs in the: _______. a) condenser b) evaporator c) compressor d) expansion device
c) compressor
To change the compressor on a system containing 40 pounds R-500, using a recycling machine that was manufactured AFTER November 15, 1993, you must isolate the compressor then: ______________. a) Simply remove the compressor b) evacuate the isolated section of the system to atmospheric pressure, then remove the compressor c) evacuate the isolated section of the system to 10 inches of vacuum and hold. If system pressure does not rise, remove the compressor d) evacuate the isolated section of the system to 15 inches of vacuum and hold. If system pressure does not rise, remove the compressor
c) evacuate the isolated section of the system to 10 inches of vacuum and hold. If system pressure does not rise, remove the compressor
On a high-pressure system ________ is an indicator of a possible leak. a) high head pressure b) low water temperature c) excessive superheat d) frequent purging
c) excessive superheat
With an air-cooled condenser on the roof of a building and the evaporator on the first floor, recovery should first occur: ___________. a) from the vapor line entering the condenser b) from the discharge of the compressor c) from the liquid line entering the evaporator d) on the suction side of the compressor
c) from the liquid line entering the evaporator
The backseating of a suction shutoff valve will close the: _______. a) suction line and compressor port b) compressor and gauge port c) gauge port d) compressor port
c) gauge port
Refrigerant leaves the receiver of a system as a: a) low pressure liquid b) low pressure vapor c) high pressure liquid d) high pressure vapor
c) high pressure liquid
A system can be evacuated to only atmospheric pressure when: ___________. a) the repair is major b) the repair is followed by an evacuation of the appliance to the environment c) leaks in the appliance make evacuation to the prescribed level unattainable d) the appliance is being disposed
c) leaks in the appliance make evacuation to the prescribed level unattainable
The fastest way to recover refrigerant from a system is to remove it in the _______ phase? a) final b) initial c) liquid d) vapor
c) liquid
To recover liquid refrigerant, you must connect one hose to the: _______. a) compressor suction valve b) compressor discharge valve c) liquid line d) top of the condenser
c) liquid line
When servicing a 60-ton packaged rooftop unit, the easiest way to check the type of refrigerant it uses is to: _________. a) use your service gauge set and a refrigerant card b) ask the owner c) look at the unit nameplate d) determine the condenser size
c) look at the unit nameplate
Heat Pumps that use R-410A should be leak checked with: ________. a) HFCs b) HCFCs to lower the cost of discarding the refrigerant c) pressurized nitrogen d) compressed oxygen
c) pressurized nitrogen
Heat pumps that have been retrofitted from R-22 to R-407C should be leak checked with: ________. a) HFCs b) HCFCs c) pressurized nitrogen d) compressed air
c) pressurized nitrogen
When servicing an operating unit that has a receiver/storage tank, the: _________. a) compressor should be isolated off b) liquid should be recovered last c) refrigerant should be recovered into the receiver d) gauge pressure should be achieved by venting
c) refrigerant should be recovered into the receiver
After reaching the required recovery vacuum on a system you must: ______________. a) immediately disconnect the recycling or recovery equipment and open the system for service b) immediately break the vacuum with nitrogen and open the system for service c) immediately pressurize the system with nitrogen and perform a leak check d) wait to see if the system pressure rises, indicating that there is still refrigerant in liquid form or refrigerant trapped in the oil
d) wait to see if the system pressure rises, indicating that there is still refrigerant in liquid form or refrigerant trapped in the oil