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115 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Which of the following statements is correct when referring to large refrigerant or nitrogen tanks |
D. All of the above are correct |
A. The protective cap must be on when the tank is not in use B. Safety goggles or glasses must be when with moving the tank C. Large tank should not be carried they should be secured to an approved cart D. All of the above are correct |
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When it is necessary to perform electrical work in an area that has a damp or wet floor which of the following can be done to minimize the chance of electrical shock |
D. All of the above |
A. Place a rubber mat on the floor B. Use a wooden ladder C. Wear insulated boots and gloves D. All of the above |
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When using a torch to braise A fitting the technician should use the proper size _______, wear _______, and always have _______ nearby |
C. Torch tips, safety glasses, fire extinguisher |
A. Copper pipe, insulated boots, fire extinguisher B. Torch tip, insulated boots, protective fire Shield C. Torch tips, safety glasses, fire extinguisher D. Acetylene tank, safety glasses, bucket of water |
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An example of a pressure vessel is _______ |
C. A cylinder containing refrigerant |
A. A small ship containing refrigerant cylinders B. The compressor in a refrigeration unit C. A cylinder containing refrigerant D. A portable dolly |
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A fusible plug is a metal fitting that has a hole drilled through it and the hole is filled with _______ |
Material with a low melting point |
A. Material with a low melting point B. Plastic C. Copper fused with brass D. A metal alloy that will burn when overheated |
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When transferring refrigerant from a cylinder to a refrigeration system or any other container you should always wear _______ |
Goggles with side shields and gloves |
A. Goggles with side shields and gloves B. Heavy protective clothing C. Rubber gloves D. Industrial steel toe shoes and an insulated cap |
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Before using a voltmeter always _______ |
Set the range selector to a setting higher than the voltage you expect to read |
A. Zero the ohms adjustment B. Touch the two leads together to ensure continuity C. Set the range selector to a setting higher than the voltage you expect to read D. Turn off the power |
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A double insulated drill |
Generally has a plastic case with the electrical connections and motor insulated within the tool |
A. Has two ground wires to ensure proper grounding B. Generally has a plastic case with the electrical connections and wiring insulated with in the tool C. Is used with a 3 to 2 prong adapter D. Has rechargeable batteries |
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In electrical circuits the grounding wire is typically |
Green or bare |
A. Black B. Red C. Green or bare D. White |
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Which of the following tools is different from the rest with respect to the shape of the network screw that it turns |
Allen wrench |
A. Open-end wrench B. combination wrench C. allen wrench D. adjustable wrench |
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A socket set is an integral part of a technician's toolbox because |
All of the above |
A. The extension allows easier access to nuts bolts and tight locations B. The ratchet handle can loosen and tighten a nut or hex head bolt with minimal movement C. There are multiple sockets that can be interchanged easily to accommodate many different size nuts and bolts D. All of the above |
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A wiring and crimping tool is used to |
Cut and strip wire |
A. Crimp tubing B. cut and strip wire C. staple low voltage wire D. Fasten installation to duct |
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Air conditioning and Refrigeration reversible ratchet wrenches are used to |
Open and close refrigerant service valves |
A. Tighten hex head sheet metal screws B. tighten flare nuts C. open and close refrigerant service valves D. tighten nuts that cannot be reached with other wrenches |
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Flare nut wrenches are used to |
Tighten or loosen nuts on copper tubing |
A. Tighten or loosen nuts on copper tubing B. open or closed refrigerant service valves C. tighten nuts that cannot be reached with other wrenches D. remove hex head screws for refrigerator cabinets |
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Tube cutters are used to |
Cut copper tubing |
A. Cut insulation from tubing B. cut iron pipe used for natural gas or liquid petroleum gas C. cut copper tubing D. cut sheet metal duct |
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A gauge and manifold assembly used in refrigeration work may include |
All of the above |
A. Compound gauge, standard gauge, manifold, valves and hoses B. either 2 or 4 valves C. a 4-way valve design using a shut off valve for each hose D. all of the above |
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A sling psychrometer |
Measures the dry bulb and wet-bulb temperatures of air |
A. Measures the dry bulb and wet-bulb temperatures of air B. measures the air velocity through a duct C. uses a microprocessor to provide information for proper air balance D. measures the quantity of air in CFM flowing through a duct |
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The halide leak detector |
Detect refrigerant leaks in a refrigeration system |
A. Detect nitrogen leaks in the refrigeration system B. is used to detect water leaks in a chilled water system C. detect refrigerant leaks in a refrigerant system D. detects air leaks in duct systems |
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An inclined water manometer is used to |
Determine air pressure in very low pressure system |
A. Determine the level of vacuum while evacuating a refrigeration system B. determine natural gas and liquefied petroleum gas pressures C. measure the operating pressure in the low side of a refrigeration system D. determine air pressure is in very low pressure system |
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A Mercury u-tube manometer is used to |
Determine the level of vacuum while evacuating a refrigeration system |
A. Determine the level of vacuum while evacuating a refrigeration system B. determine natural gas and liquefied petroleum gas pressures C. measure the operating pressure on the low side of a refrigeration system D. Analyze air flow problems in an air duct distribution system |
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For fastening two pieces of rough lumber together the nail used would be a |
Common nail |
A. Finishing nail B. Common Nail C. Roofing nail D. Masonry nail |
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For recessing the nail for filling and finishing the wood surface the nail used would be a |
Finishing nail |
A. Finishing nail B. common Nail C. Roofing nail D. masonry nails |
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For fastening a pipe strap to a cement wall at the nail used would be a |
Masonry nail |
A. Finishing nail B. common Nail C. roofing nail D. masonry nail |
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To fasten a duct hanger strap to a floor joist the nail used would be a |
Roofing nails |
A. Finishing nail B. common Nail C. roofing nail D. masonry nail |
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To secure a flexible duct into a duct collar the best fastener would be a |
Nylon strap |
A. Sheet metal screw B. Iron wire C. nylon strap D. Duct tape |
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An outward clinch Tacker is used to |
Spread the end of a staple outward |
A. Bend wire on a pipe hook B. install a pop rivet C. drive a roofing nail D. Spread the ends of a staple |
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The hole drilled in sheet metal for a tapping screws should be the approximate size of |
The thread root diameter |
A. The thread diameter B. The thread root diameter C. the same diameter D. none of the above |
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In the machine screw Dimensions "5/16 - 18 UNC - 2" , 5/16 indicates the |
Outside thread diameter |
A. Length B. number of threads C. outside thread diameter D. head diameter |
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In the tapping screw Dimensions "6 - 20 x 1/2 type AB, slotted hex, the term 20 indicates the |
Number of threads |
A. Length B. number of threads C. thread diameter D. head diameter |
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If a technician needed 5/8 ACR for an installation and was located near only a plumbing supply house what size and type of pipe should he ask for |
1/2 inch ID copper |
A. 5/8 ACR B. 1/2 PVC C. 1/2 ID copper D. 5/8 PVC |
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Pipe threads are standardized by the ANS, ANS stands for |
American National Standard |
A. All nominal standard B. American National Standard C. All new steel D. apparent nominal standard |
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The size indicated for the diameter of Type L copper tubing used for plumbing is the approximate ________. |
Inside dimension |
A. Inside Dimension B. outside Dimension C. wall thickness D. none of the above |
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95/5 solder should be used _______. |
On the low side of the system |
A. On the high side of the system B. on the low side of the system C. when there are extreme changes in pressures and temperatures D. always |
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The size indicated for the diameter of ACR copper tubing is the approximate |
Outside diameter |
A. Inside diameter B. outside diameter C. wall thickness D. none of the above |
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Brazing is done at _______ soldering |
Higher temperatures than |
A. The same temperature as B. Lower temperatures than C. higher temperatures than D. temperature that can be higher or lower than |
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When soldering or brazing The solder is |
Melted by heat from tubing and fittings |
A. Heated directly by the flame of the heat Source B. heated by the surrounding C. used to oxidize metal D. melted by heat from the tubing and fitting |
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The proper type of flame from an oxy acetylene torch for silver brazing is |
Neutral Flame |
A. Long tail flame B. neutral flame C. oxidizing flame D. carbonizing Flame |
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For cleaning ACR copper tubing before soldering a material that can be used is |
All of the above |
A. Steel wool B. Carborundum cloth C. sand cloth D. all of the above |
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Molten solder flows between the two base Metals being soldered because |
Of capillary action |
A. The atmospheric pressure pushes it in B. of capillary action C. there are no surface pores in the base metal D. the tubing surface melts and the pressure differential forces it in |
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When moisture is present in a refrigeration system it will react with the refrigerant in the oil to form |
Acid |
A. Carbon dioxide B. acid C. carbon monoxide D. all of the above |
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Which of the following represents the lowest vacuum |
1000 microns |
A. 10 psi B. 5" VAC C. 5 PSIG D. 1000 microns |
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To pull a vacuum means to |
Lower the pressure in a refrigeration system below atmospheric |
A. Raise the pressure in a refrigeration system B. lower the pressure in a refrigeration system below atmospheric C. allow refrigerant to escape into the atmosphere D. condense the gas in the system |
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A compound gauge |
All of the above |
A. Indicates pressures above 14.696 psia B. indicates pressures in inches HG below atmospheric pressure C. is one of the two gauges on a typical gauge manifold D. all of the above |
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A micron gauge is used to measure |
Absolute pressure below one millimeter HG |
A. Atmospheric pressure at high altitudes B. atmospheric pressure at sea level C. absolute pressure below one millimetre Hg D. high pressure in a refrigeration system |
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The best method of leak checking is when the refrigeration system is |
Standing with dry nitrogen pressure of 150 PSIG in the system |
A. In a vacuum B. open to the atmosphere C. operating with all fans activated D. standing with dry nitrogen pressure of 150 PSIG in the system |
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Noncondensable gases |
Are undesirable in a refrigeration system |
A. Are desirable in refrigeration system B. are undesirable in a refrigeration system C. condenser readily under normal atmospheric conditions D. help in pulling a vacuum |
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What is the most accurate instrument for checking a deep vacuum |
Electronic vacuum gauge |
A. compound gauge B. Mercury "U" tube manometer C. Mercury barometer D. electronic vacuum gauge |
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A multiple vacuation means that |
You pull a vacuum on a refrigeration system more than once allowing refrigerant or nitrogen into the system between each procedure |
A. You connect 3 vacuum pumps simultaneously to a refrigeration system and pull a vacuum N. you pull a vacuum on three different systems at the same time C. you pull a vacuum on a refrigeration system more than once allowing refrigerant or nitrogen into the system between each procedure D. there must be more than one system operating before vacuum can be pulled |
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Moisture in a liquid state must be _______ before it can be removed with a vacuum pump |
Vaporized |
A. Vaporized B. condensed C. cooled D. solidified |
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True or false when working in the machine room safety glasses should not be worn because they can follow up and impede your eyesight |
False |
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True or false if you are a refrigeration technician a warm coat and gloves should be in your truck even in the middle of the summer |
True |
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True or false aluminum ladders are safe to use around electrical equipment as long as they have insulation pads on the bottom of the rungs |
False |
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True or false It is possible that your hand would suffer frostbite if it comes in contact with liquid R22 when accidentally released in refrigerant into the atmosphere (an illegal procedure) |
True |
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True or false as long as the torch is kept moving below the level of the liquid refrigerant in the cylinder so as not to create a hotspot it is ok to heat the cylinder in this manner |
False |
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True or false to insure proper operation of an oxygen cylinder regulator make sure no oil residue is present |
True |
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True or false A Wall anchor is a one-time fastener |
False |
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True or false when tubing is cut with a tubing cutter a burr is produced in the process. This slight decrease in the inside diameter of the tube can adversely affect the operation of the system |
True |
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True or false 95/5 tin-antimony solder can be used in any part of a refrigeration system |
False |
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True or false The end of a piece of steel pipe is reemed after it is cut with a pipe cutter to make it easier to start the thread die |
False |
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True or false After repairing a system that has had an electrical motor failure (compressor burned out) it is good field practice to reuse to recovered refrigerant in that system |
False |
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True or false Air entering a refrigerant system can eventually lead to compressor failure |
True |
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True or false while under a deep vacuum any liquid water under the oil in the motor-compressor assembly can be removed by operating the compressor motor for several seconds without any adverse effect on the system |
False |
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True or false The oil in a vacuum pump should be changed after each time it is used |
True |
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Oil must never be used around a _______ cylinder |
Oxygen |
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The easiest way to move equipment across the roof is to use |
Plywood and rollers |
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Power tools that are not double insulated must have three prong plugs to ensure that the tool is properly |
Grounded |
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Refrigerant from a refrigeration system that has a burned out motor compressor assembly can be dangerous because it could contain a high concentration of |
Acid |
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The tool used to create pipe threads on the outside of a pipe is called a |
Die |
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The tool used to create internal threads is called a |
Tap |
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After brazing a joint in a very tight location the technician would use an ___________ to determine if the joint is properly brazed |
Inspection mirror |
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Evacuating the system is accomplished with a _______ and helps to remove ______ and ______ from a system |
Vacuum Pump, Air, noncondensables |
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A vacuum pump removes _______ and _______ from a refrigeration system |
Air, non condensables |
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An instrument that can be used to determine the relative humidity of air is the |
Psychrometer |
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The most common Fastener used for securing an object to a solid concrete slab would be |
Anchor Shield |
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To secure two pieces of sheet metal together a technician may use a _______ since no pre-drilling is required |
Self tapping screw |
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The term used to designate the size of a nail is _______ and the symbol is _______. |
Penny, d |
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The copper tubing used in the field piping of refrigeration system is type |
ACR |
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One reason for insulation on a suction line is to help maintain the proper |
Superheat |
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In the thread specification 1/2 - 14 npt, the one half is the |
Outside thread diameter |
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In the thread specification 1/2 - 14 npt, the 14 stands for |
Number of threads |
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In the thread specification 1/2 - 14 npt, the npt stands for |
National pipe taper |
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When using a standard pressure test for leak checking _______ should never be used since an explosive mixture can be created |
Air |
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______ microns is equal to 1 millimeter HG |
1000 |
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The temperature sensitive resistor commonly used on vacuum gauges is called a |
Thermistor |
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Sludge is produced when _______, _______ and _______ are present in the system |
Moisture, acid, oil |
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There are _______ microns in one millimeter HG |
1000 |
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Only two substances should be in the refrigeration system for proper operation. They are _______ and _______ |
Oil, refrigerant |
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A deep vacuum involves reducing the pressure in a refrigeration system to a micron gauge reading of _______ or below |
500 microns |
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Why should a technician not wear jewelry and metallic watches while working on a system |
Shock or snag hazard |
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When turning off the electrical power at a disconnect panel to work on an electrical circuit, what should you do to ensure that no one will turn the power on unless you have finished and are ready |
Lockout, Tag out |
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Why should a ground fault interrupter be used with a portable electric tools |
stops electric flow, protects against shock |
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For what is a soldering gun used for |
Electrical connections |
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Name three types of fastening devices that can be used to mount an object to a hollow wall |
Plastic wall anchors, anchor bolt, toggle bolt |
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The two types of sheet metal screws would be 1) _______, 2) _______ |
Self drilling, self tapping |
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Why should some refrigerant lines be insulated |
Prevent system from absorbing excess heat, prevents condensation |
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What are two purposes for using insulation on the suction line |
Maintain superheat, prevent condensation |
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When soldering, what is the flow of molten filler material between the two base Metals called |
Capillary attraction |
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When making a swage joint, what should the depth of the a large portion of the tube be |
Equal to the diameter of the original tube |
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Why is nitrogen considered a "noncondensable" gas |
Because it cannot be condensed |
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Give three reasons why leak checking by pulling a vacuum is not a good for practice |
Can't detect leak, pulls in air and noncondensables, dirt and debris will clog the leak |
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Why is it a good idea to remove Schrader stems from service valves prior to evacuation |
Restriction |
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Why must all valves be opened when an evacuation is performed |
Non condensables can get trapped in the system |
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Why is refrigerant not used for a system standing pressure test |
Pressure/temperature differential |
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Hacksaw |
Metal stock |
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Tubing cutters |
Soft-drawn copper tubing |
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Utility knife |
Plasterboard/Fiberboard |
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Stripper and crimping tool plastic |
Copper wire |
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Tubing shear |
PVC |
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Operation that causes one end of a copper tube to expand at an angle for flare nut connection to system |
Flaring |
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Operation of heating and cooling tubing to make it softer |
Annealing |
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Accomplished at temperatures under 800 degrees Fahrenheit |
Soldering |
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Removal of burrs and rough edges from tubing |
Reeming |
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Accomplished at temperatures above 800 degrees Fahrenheit |
Brazing |
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Caused by excessive bending and straightening of tubing |
Work hardening |
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Operation that allows two tubes of equal diameter to be joined together |
Swaging |
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