Service Practice 3: Part 2
The evaporation temperature of r-134a at 7 psia is ___ degrees F
-15
When scrapping a disposable cylinder, the cylinder pressure must be at _____ psi.
0
The smallest container in which refrigerants may be sold to a section 608 certified technician is ______ lb.
1
Equipment manufactured after November 15, 1993 that is used to recover refrigerant from small appliances for the purpose of disposal must be able to recover _____, according to the standard
1. 80% of the refrigerant with an inoperative compressor. 2. 90% of the refrigerant with an operative compressor.
When addressing consumer questions regarding additional service expense due to recovery efforts, technicians must
1. Explain to the customer that recovery is necessary to protect human health and the environment. 2. Explain to the customer that refrigerant recovery is required by law. 3. Remind the customer that all professional service personnel are duty bound to follow the law and protect the environment.
When using recovery cylinders and equipment with Schrader valves, it is critical to
1. Inspect the Schrader valve core for bends and breakage. 2. Replace a damaged Schrader valve core to prevent leakage. 3. Cap the Schrader ports to prevent accidental damage of the valve core.
When transferring refrigerant to a pressurized cylinder, the safe filling level can be controlled by
1. Mechanical float devices. 2. Electronic shutoff devices. 3. A scale
Before shipping any used refrigerant in a cylinder, it is necessary to
1. Properly label the refrigerant container. 2. Properly complete shipping paperwork. 3. Check that the refrigerant container meets department of transportation standards.
Reason to obtain an accurate pressure reading of refrigerant inside a recovery cylinder is that the pressure reason can indicate
1. That there is excessive air or other non-condensable in the cylinder. 2. That the refrigerant has been broken down (made unusable)
When ____, an excessive pressure contain on the high-pressure side of a self-contained (active) recovery device will exist.
1. The recovery container inlet valve has not been opened. 2. There is excessive air in the recovery container.
Full storage cylinder of recovered r-22 at normal room temperature (about 75 degrees F), with no non-condensbales present, should be pressurized to _____ psi.
130
When using recovery and recycling equipment manufactured after November 15, 1993, technicians must evacuate an appliance component containing more than 200 lb of CFC-12 to ____ before making a major repair.
15" hg vacuum
Reusable containers for refrigerants that are under high pressure (above 15 psi) at normal ambient temperature must be hydrostatically tested and date stamped every ____ years.
5
The refrigerant pressure of a storage cylinder with r-12 refrigerant at room temperature (70 degrees F) is approximately ____ psig.
70
Full storage cylinder of recovered r-12 at normal room temperate (about 75 degrees F) with no non-condensables present, should be pressurized to _____ psi.
75
Refillable refrigerant cylinder must not be filled above ___ % of its capacity by weight.
80
Small appliance recovery equipment manufactures on or after November 15, 1993 must be certified to be capable of recovering ___ % of the refrigerant when the compressor is operating, or achieving a ____ " hg vacuum under the conditions of Ari-740 - 1993
90 ; 4
Because small amounts of CF and HCFC refrigerant have no odor, when pungent oder of detected during refrigerant recovery or system repair,
A compressor burnout has likely occurred.
When transporting cylinders containing used refrigerant, DOT requires that technicians
Attach DOT classification tags.
Refrigerant inside a recovery cylinder must be allowed to stabilize to room temperature
Because comparisons to a pressure-temperature chart can only be made if both pressure and temperature are stable and known
After liquid refrigerant has been recovered from an appliance, any remaining refrigerant vapor is
Condensed by the recovery system for removal.
Refrigerant should be removed from the condenser outlet when the
Condenser is below the receiver.
Before transferring refrigerant to an empty storage cylinder, the
Cylinder must be evacuated.
A refrigerant label is placed on a
Cylinder to identify gross weight.
Portable refillable tanks or containers used to ship CFC and HCFC refrigerants obtained with recovery equipment form small appliances must meet ___standards
Department of transportation
Proper disposal of refrigerant cylinders is accomplished by
Ensuring that all refrigerant is recovered and that the cylinders are rendered useless, then recycling the metal.
A technician is changing the compressor of a system containing 40 lb of r-502. The recycling equipment being used was manufactured after November 15, 1993. In addition to isolating the compressor as much as possible;e, the technician must
Evacuate the isolated section of the system to 10 hg vacuum, hold the vacuum, and remove the compressor if system, pressure does not rise.
With an air-cooled condenser on the roof of a building and the evaporator on the first floor, refrigerant recovery must start
From the liquid line entering the evaporator.
Before beginning a refrigerant recovery procedure, a technician must
Know the type of refrigerant that is in the system.
Appliances containing CFC refrigerants need only be evacuated to atmospheric pressure when
Leaks in the appliance make evacuation to the prescribed Lebel unattainable.
Technicians save time recovering refrigerant from a high-pressure system by removing as much of the refrigerant as possible in the state
Liquid
In a high pressure system, to recover liquid refrigerant, a technician must connect one recovery machine hose to the
Liquid line
Upon completing the transfer of liquid refrigerant between the recovery unit and the refrigeration system, a technician must guard against trapping
Liquid refrigerant in the compressor or between service valves.
When r-500 is recovery from an appliance, r-500
Must be recovered into a separate recovery vessel that is clearly marked to ensure that mixing of refrigerants does not occur.
When recovering refrigerant into a non-pressurized container from a refrigerator with an inoperative compressor, it is
Necessary to heat and stroke the compressor sharply several times while using a vacuum pump.
Technicians may use a disposable cylinder to recover refrigerant
Never
Disposable refrigerant containers are used for ____ refrigerant.
New
____ refrigerant(s) may be recovered into a recovery cylinder.
Only one type of
The removal of refrigerant from a system can be conducted more quickly by
Packing the recovery vessel in ice.
Technicians providing service work for systems with r-12, r-502, and r-134a refrigerants must provide special hoses, gauges, vacuum pump, recovery machine, and oil containers to be used with ____ refrigerant (s)
R-502
Technician using a recovery/recycling machine to recover r-502 refrigerant must ____ before recovering refrigerant from a system with r-22 refrigerant
Recover as much of the r-502 from the recovery machine as possible, change the filter and evacuate.
While servicing a system, a technician discovers that r-502 refrigerant was added to a system with r-22 refrigerant the technician must
Recover the refrigerant into a separate tank.
Refrigerant cylinder that has a gray body and a yellow top indicates the cylinder is designed to hold
Recovered refrigerant
Recovering refrigerant from a system in a. vapor state will minimize the loss of
Refrigerant oil
When an operating high-pressure system has a receiver (storage tank) that requires service,
Refrigerant should be recovered from the recivever.
Heaters used on a refrigerant container speeds up the transfer of ____ to the chiller
Refrigerant vapor
_____ is/are not a method or device presently used for monitoring the 80% fill level in a recovery tank
Sight glasses.
Care must be taken not to overfill reusable containers because
The internal pressure of the cylinder may rise in heated areas an cause an explosion.
System with a hermetically sealed compressor has the potential to overheat the recycling or recovery equipment is used to draw deep vacuums because
The motor relies on the flow of refrigerant through the compressor for cooling.
When recovering refrigerant form a system that experiences a compressor burnout, the technician must watch for signs of contamination in the refrigerant and oil because
The system will have to be flushed out if contaminates are present.
The main reason why a technician must never heat a refrigerant storage or recovery tank with an open flame is that
The tank may explode seriously injuring people in the vicinit.
To speed up the recovery process and ensure that all refrigerant has been removed for a frost-free refrigerator,
Turn the defrost heater of the system on to vaporize any trapped liquid.
Refrigerant cylinders must be shipped in the _____ position
Upright
Technicians must help release trapped refrigerant from the compressor oil during refrigerant recovery when
Using a system dependent (passive) recovery device on small appliances with a non operating compressor.
After achieving the required recovery vacuum on an appliance, technicians must
Wait a few minutes to see if the system pressure rises, indicating that there is still refrigerant in a liquid state or in the oil.
The department of transportation regulations-49 car, require that the ____ be recorded on the shipping paper for Hazard class 2.2, nonflammable compressed gases.
Weight of each cylinder.