The EPA defines major repairs as “maintenance, service, or repair that involves removing appliances. Access to this page has been denied because we believe you are using automation tools to navigate the website. System vacuum level is measured with __________. The capture and ultimately elimination of the use of chlorofluorocarbons is taking place in the United States.
Fluorine and Carbon When using recovery and recycling equipment manufactured AFTER November 15, 1993, technicians must evacuate a component of an appliance that contains very high pressure refrigerants, such as CFC-113 and -503 to ______ mercury vacuum before performing a major repair, regardless of the amount of refrigerant in the system. An example of an HCFC refrigerant is _______. To decrease dehydration time Each chlorine atom in the stratosphere can C. One Hundred Thousand After completing the transfer of liquid refrigerant between the recovery unit and the refrigeration system, you should be careful to avoid trapping liquid refrigerant between the service valves because__________.
There is no typical hose pressure relief valve and liquid coolant trapped in the hose could build up significant pressure and rupture hose B. Low-loss accessories required since January 1992 C. There is no reason not to trap liquid coolant in the hose as it will prevent coolant venting. A ______ refrigerant has a range of boiling points or dew points throughout the evaporator and condenser, respectively.
The term used to describe this is temperature, slip, or slip temperature. Purge coolant to ambient air and dispose of cylinders in the trash. Ensure that all coolant is recovered and cylinders are rendered useless, and then recycle metal. Add nitrogen to the cylinders, so you have a leak control gas D.
Compressed air filling for repairing flat tires. When using recovery and recycling equipment manufactured AFTER November 15, 1993, technicians must evacuate an appliance containing MORE than 200 lb of R-22 at _____ mercury vacuum before performing a major repair. HFCF refrigerants cause what amount of damage to the stratospheric ozone layer compared to CFC refrigerants. Use OSHA Approved B Containers.
What kind of problem is ozone depletion in the stratosphere? Under EPA regulations, regenerated refrigerant must meet purity standards before it can be resold. Chlorofluorocarbons (CFCs) consist of ___, ___ and ___. Carbon, Fluorine, and Other Chemicals A device that removes air and other non-condensable elements from the refrigerant system is usually located_____. At the inlet of the evaporator D.
Very High Pressure Appliances CFR _____ 49 requires that the number of cylinders for each gas be recorded in the shipping document for hazard class 2.2 Non-flammable Compressed Gases. At high temperatures (i.e. It is only necessary to recover the amount of refrigerant that will naturally come out of the system. It is not necessary to recover it, as the refrigerant is likely to be contaminated.
It is necessary to expel the coolant from the oil with pressurized dry nitrogen. DOT regulations, 49 CFR, require __________ to be recorded on the shipping document for hazard class 2.2, non-flammable compressed gases? B. Total cubic feet of each C gas. Number of cylinders for each gas D.
Total Weight of All Cylinders When filling a charging cylinder, the coolant that is vented from the top of the cylinder______. Which of the following definitions best describes the small device recovery category? AT. Includes all products manufactured, charged and hermetically sealed in a factory with 2 pounds or less of coolant. Includes products manufactured, filled and hermetically sealed in a factory with 5 pounds or less of coolant.
Includes miniature refrigerators, freezers, dehumidifiers and some split central air conditioning systems. Includes all appliances loaded with 5 pounds or more of coolant. Small appliances serviced by recovery equipment manufactured after November 15, 1993 should be able to _________. It is generally recommended that pierce-type valves be used only on ____ tubes.
Recover 90% of refrigerant when compressor is running or achieve 4-inch vacuum under conditions of ARI 740-1993 B. Recover 80% of the refrigerant when the compressor is running C. Recover 95% of the refrigerant when the compressor is running or achieve a 10-inch vacuum under the conditions of ARI 740-1993 D. Recover 75% of the refrigerant when the compressor is running EPA regulations define a small appliance as one that is manufactured, charged and hermetically sealed in the factory and contains ____ pounds or less of refrigerant.
Only to be used if mixed with R-22 Refrigeration technical certification currently has_______. A two-year recertification requirement There is a huge leak of R-22 in a confined area, which of the following statements is true? AT. Safety goggles and butyl-lined gloves are sufficient protection. Leave the area and return with a self-contained breathing apparatus.
Dust masks are enough to filter coolant. After installing and opening a perforating access valve, if the system pressure is ______, do not begin the recovery procedure. Which of the following requirements should recovery devices manufactured BEFORE November 15, 1993 meet the following requirements? AT. Capable of recovering 80% of the refrigerant whether the compressor is running or not, achieving a 4-inch vacuum under conditions of ARI 740-1993 B.
Capable of recovering 70% of the refrigerant if the compressor is running or achieves a 4-inch vacuum under conditions of ARI 74-199300 C. Capable of recovering 10-inch vacuum under conditions of ARI 74-1993 D. No requirements; this equipment would be considered exempt. Because _____, all appliances must be equipped with a service feature or other device used when adding or removing coolant from the appliance.
For small appliances, this service port is generally a straight piece of pipe that is entered via a piercing access valve. After recovering refrigerant from a sealed system, if nitrogen is used to pressurize or expel debris from the system, nitrogen ______. It can be ventilated, since the air is 80% nitrogen B. Can't vent, as nitrogen destroys ozone C.
Must be recovered and recycled Small appliances containing HCFC refrigerants can be evacuated to atmospheric pressure when _____. The repair is followed and the device is evacuated to environment C. Leaks make evacuation at the prescribed level unattainable D. The appliance is being removed from non-condensables in a refrigeration system, resulting in a _______.
Which of the following would be considered a major repair by the EPA? B. Replace an Evaporator Coil EPA regulations require that all appliances containing more than 50 lbs of refrigerant (except commercial and industrial process refrigeration) be repaired when the leak rate exceeds ___ load per year. What would be the result of a leak in a high-pressure system? EPA regulations require that leaking commercial and industrial process refrigeration systems containing 50 lb or more of refrigerant be repaired when the leak rate exceeds ___ percent of load per year. If a service technician's recovery equipment was manufactured BEFORE November 15, 1993, he must evacuate a refrigeration system containing 10 pounds of R-500 to _____.
Technicians are certified to recover refrigerant during the maintenance, service, or repair of high-pressure equipment if they receive a passing score on any of the following exams. All of the above except R-134a G. All of the above except R-123 When evacuating a vapor compression system, the vacuum of ________ microns. System dependent recovery equipment CANNOT BE used when the appliance contains more than ____ pounds of refrigerant.
Replacing _____ is a repair that would always be considered important under EPA regulations. Temperature is above 95 F C. The load is more than 15 pounds D. Charge is more than 5 pounds When using recovery and recycling equipment manufactured AFTER November 15, 1993, technicians must evacuate an appliance containing LESS than 200 pounds of CFC-12 at _____ mercury vacuum before performing a major repair.
What is the first thing to do when a new air conditioning system has been assembled for the first time and is ready for testing? AT. Pressurize the system with nitrogen and perform a leak test. Perform a standard C vacuum test. Pressurize with R-12 and Leak Test Recovery of refrigerant from a heat pump in the vapor phase will minimize the loss of _____.
Removing the refrigerant charge from a system can be accomplished more quickly by ____ the recovery tank. Refrigerant recovery from a system in ___ will minimize system oil loss. What is the most likely source of water for a recovery unit condensation coil? When you have no other option but to use a trace refrigerant gas, which refrigerant should be used for leak detection? With an air-cooled condenser on the roof of a two-story building and the evaporator on the first floor, it would be best to start the recovery _____. From the discharge of compressor C.
From the liquid line entering the evaporator D. From the liquid line leaving the condenser, how would you determine when enough vapor has entered the refrigeration system before charging it with coolant liquid? AT. When the saturation temperature is above the freezing point of water. When the pressure relief valve is slightly vented.
The PRIMARY purpose of a purge unit in a CFC-11 cooler is ________. Condensing system C water. Draw air out of system E. Eliminate non-condensables from system F.
Purge solid particles from the system Because a _____ system operates below atmospheric pressure, system leaks cause air and other contaminants to seep into the system. When recharging an R-11 system, the first step is to charge the unit with refrigerant vapor. The refrigerant vapor is charged to the system until the refrigeration saturation temperature is above ______. Technicians are certified to recover refrigerant during maintenance, service, or repair of low-pressure equipment if they receive a passing score on any of the following exams.
According to the EPA, what method can be used to pressurize a system to open it for minor repair? When evacuating refrigerant from a low-pressure chiller, using a push-pull method, the high-pressure cut-off of the recovery unit should be set to ______. EPA believes the most effective method to check for leaks in low-pressure refrigeration machines is with ______. Replacing ___ is a repair that is always considered important under EPA regulations. When charging an evacuated refrigeration system, why is refrigerant vapor reintroduced into the cooling system before the coolant liquid? AT.
Prevent rupture disc failure. Vapor charging is faster than liquid. Liquid loading is more difficult to control than vapor loading. Liquid that is loaded in a deep vacuum boils and can lower temperatures enough to freeze water in the tubes.
Return recycled refrigerant to unit B. Removes air and non-condensables from system C. They have been banned by the EPA C. Must be equipped with low-loss accessories.
Must be able to handle more than one coolant. Under EPA regulations, one of the following actions is allowed to be taken to pressurize an R-11 system for the purpose of opening the system for minor repairs. Use an open flame gently applied to the capacitor C. Use a propane or acetylene-air torch, but not an oxygen-acetylene torch, as it would be too hot.
When recharging a refrigeration system with R-11, _____ vapor pressure is required in the housings before charging them with liquid. EPA defines _____ as maintenance, service, or repair that involves removing the compressor, condenser, evaporator, or coil from the auxiliary heat exchanger of the appliance. EPA regulations require that leaking commercial and industrial process refrigeration containing more than 50 pounds of refrigerant be repaired when the leak rate exceeds ___ of the load per year. According to the EPA, when removing oil from a low-pressure system, the temperature must be so warm to reduce the amount of refrigerant contained in the oil.
When testing for leaks in a low-pressure centrifuge with nitrogen, the maximum test pressure is ___? A rupture disc in a recovery vessel for low-pressure refrigerants relieves ____. In a centrifugal system, the suction of the purge unit is connected to the ___. For a permanent vacuum test in accordance with ASHRAE Guideline 3-1996, if the pressure rises from 1 mm Hg to a level greater than ____, the system should be checked for leaks. Hydrostatic tube tests are used for _____.
Determine if a tube has a leak C. Remove water from system D. Vent Water to Atmosphere Appliances containing coolant can be evacuated at ___, when leaks in the appliance make evacuation to the EPA-prescribed level unattainable, since air would be drawn into the recovery device from the environment. EPA regulations require that all appliances containing more than 50 lbs of refrigerant (except commercial and industrial process refrigeration) be repaired when the leak rate exceeds ___ load per year.
The EPA defines major repairs as “maintenance, service, or repair that involves removing the appliance. When using recovery and recycling equipment manufactured AFTER November 15, 1993, technicians must evacuate an appliance containing LESS than 200 lb of CFC-12 at _____ mercury vacuum before performing a major repair. Any person who, in the course of servicing, servicing or repairing an appliance (except MVACs), can reasonably be expected to violate the integrity of the refrigerant circuit and, therefore, release refrigerants to the environment. Maintenance, service or repair involving removal of the compressor, condenser, evaporator, or auxiliary heat exchanger coil from the appliance.
Recovery requires specialized machinery that is not available at a particular job site or auto repair shop. Everyone who opens appliances for maintenance, service, or repair must have at least one certified, autonomous recovery equipment available at their workplace. Examples of an irreparable defect would be if the coils have rusted or if a hole in the coil tubing is so large that it cannot be closed by repairing it. .
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