Term
Which of the following repreent and different temperature than the other 3?
A) 15 C
B) 59 F
C) 475 K
D) 519 R |
|
Definition
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|
Term
Of the following chioces, the warmest temperature is
A 20C
B 303K
C 501R
D 77F |
|
Definition
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Term
Pure water boils at a temp of 212F at what standard condition?
|
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Definition
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Term
The temperature on the farinheit scale where all molecular biology activity stops is
|
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Definition
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Term
The temperature on the celsius scale where all molecular activy stops is
|
|
Definition
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|
Term
as the temperature of a material increases, the molecules in the material _______
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Definition
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|
Term
How many BTUs are required to change on pound of ice at 20F to steam at 220F?
|
|
Definition
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|
Term
How many BTUs are required to change five pounds of ice at 20F to steam at 220F
|
|
Definition
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|
Term
How many BTUs must be removed from one pound of water at 200F for it to end up as ice at 30F?
|
|
Definition
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|
Term
The ammount of heat needed to change the temperature of a suvstance will cary with the type of substance.
The heat quality is call the _______ of the substance
|
|
Definition
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|
Term
| The standard Atmospheric pressure at sea level is |
|
Definition
|
|
Term
|
Definition
pounds per square inch absolute guage |
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|
Term
| A bourdon tube is often found in a(n) _____ |
|
Definition
|
|
Term
The Farenhite scale is used in English measurement system in the USA
T or F |
|
Definition
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|
Term
The difference in the level of heat between two substances will determine the heat transfer rate
T or F |
|
Definition
|
|
Term
Both sensible heat and latent heat transfers can be read with a thermometer
T or F |
|
Definition
|
|
Term
| The fahrenheit scale is called the ______ |
|
Definition
|
|
Term
| Atmospheric pressure in inches of mercury (" Hg) decreases _______ per 1000 feet increase in elevation |
|
Definition
|
|
Term
| A solid material exerts a pressure of force _____ |
|
Definition
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|
Term
| a liquid material exerts a pressure or force _______ |
|
Definition
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|
Term
| If the temperature remains constant and the volume that a gas occupies increases the pressure will________ |
|
Definition
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|
Term
The volum of gas varies inversly with the absolute pressure, provided the temperature remains constant
This is called ______ |
|
Definition
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|
Term
At a constant pressure, the volume of a gas varies as to the avsolute temperature and at a constant colume the pressure of the gas varies directly witht the absolute temperature
This is called __________ |
|
Definition
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|
Term
The total pressure of a confine mixture of gasses is the sume of the pressures of each of the gases in the mixture
This is known as__________ |
|
Definition
|
|
Term
| A helicoptor is lifting an 800 pound unit at a rate of 200 feet per minute. How may horsepower of work energy is the helicoptor using in the process? |
|
Definition
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|
Term
| The unit used to measure electrical power is the |
|
Definition
|
|
Term
| One watt of electrical energy is equal to how many BTU's? |
|
Definition
|
|
Term
How many watts of electrical power are equal to one horsepower?
|
|
Definition
|
|
Term
Specific volume is the term used to indicate the space a weight of gas will occupy
T or F |
|
Definition
|
|
Term
as heat is applied to a closed container containing a gas, the pressure inside the container will decrease
T or F |
|
Definition
|
|
Term
An example of a fossil fuel is hydrogen
T or F |
|
Definition
|
|
Term
Heat is a form of energy because of the motion of the molecules
T or F |
|
Definition
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|
Term
| The three basic stages of material are _________, _________, and ________ |
|
Definition
|
|
Term
| The law that states that "energy is neither created or destroyed, but can be converted from one form to anoher" is called |
|
Definition
| The Law of Energy Conservation |
|
|
Term
| Most of the energy we use comes from something we have on Earth. The only "new" energy we get comes from the __________ |
|
Definition
|
|
Term
|
Definition
| A molecule is composed of atoms and cannot be broken down without changing its chemistry |
|
|
Term
|
Definition
The quantity of something per unit measure
Is the ratio of a substane mass to volume compared to water |
|
|
Term
| What happens when room temerature soda is poured into a glass of ice? |
|
Definition
| The ice melts because it is absorbing the heat from the soda |
|
|
Term
| Ice melts in Ice boxes because? |
|
Definition
| Heat flows through insulated walls, heat enters when the door is opened, heat enters when warm food is placed in the icebox |
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|
Term
| High Temperature refridgeration is produced by |
|
Definition
| An air conditioning system |
|
|
Term
| Refridgeration can be described as |
|
Definition
| the process of removing heat from a place where it is not wanted to a place where it makes little or no difference |
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|
Term
| The ________ relationship correlates the vapor pressure and the boiling point of water and is the basis for controlling the cooling systems temperatures |
|
Definition
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|
Term
| The ______ are used to change the vapor to a liquid and the liquid form back into a vapor in a refridgeration cycle |
|
Definition
|
|
Term
| The Evaporator in a Refridgeration system _______ |
|
Definition
| Absorbs heat from the product to be cooled |
|
|
Term
| Reciprocating compressors have ______ |
|
Definition
|
|
Term
|
Definition
| rejects heat from the refridgerent |
|
|
Term
| When a refridgerent enters the compressor it is a ________ and when it leaves the compessor ir is a _________ |
|
Definition
low pressure, low temperature superheated vapor
high pressure, high temperature, superheated vapor |
|
|
Term
| The compressor in a refridgeration system __________ |
|
Definition
| Raises the boiling point of the refridgerant and pumps the refridgerant throughout the system |
|
|
Term
| Good ventilation is important when working around refridgeration equipment because modern refridgerants________ |
|
Definition
| Are heavier than air and may displace the oxygen around you |
|
|
Term
Which of the following refridgerents has the lowest boiling temperature at atmospheic pressure
A r-12
B r-22
C r-134a
D r-502 |
|
Definition
|
|
Term
| The law requires technicans to recover refridgerant from all refridgeration systems so that they |
|
Definition
Will not be released into the atmosphere
may be used again
may be reclaimed for future use
|
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|
Term
The evaporator in a refridgeration system must be colder than the refridgerated space in order to absorb heat
T or F |
|
Definition
|
|
Term
Id a cylinder of R-22 is moved from a truck at 100F to a 80F shop the quantity of liquid refridgerant remains the same
T or F
|
|
Definition
|
|
Term
The evaporator can be thought of as a heat sponge
T or F |
|
Definition
|
|
Term
| The refridgerant vapor picks up additional heat as it flows from the evaporator to the compressor. The heat is picked up from the ___________ |
|
Definition
|
|
Term
| The _______ is another positive displacement compressor and is used for larger air conditioning and refridgeration applications |
|
Definition
|
|
Term
| The ammount of heat a refridgerant contains with -40F as the 0 heat contect reference point is called |
|
Definition
|
|
Term
Which of the following statements are correct when referring to large refrigerant or nitrogen tanks?
A The protective cap must be on
B Saftey Goggles or glasses must be worn when moving
C Large Tanks should not be carried, but moved with an approved cart
D All of them |
|
Definition
| All of the above are correct |
|
|
Term
| An example of a pressure vessel is |
|
Definition
| a cylinder containing refrigerant |
|
|
Term
| An R-22 cylinder containing enough refrigerant to have liquid refrigerant in it, is in a truck with a temperature of 120F. What would be the PSIG pressure in the cylinder? |
|
Definition
|
|
Term
| A fuseable plug is a metal fitting that has a hole drilled thought it and the hole is filled with ________ |
|
Definition
| A material with a low melting point |
|
|
Term
| When transferring refrigerants from a cylinder to a refrigeration system or any other container, you should always wear _________ |
|
Definition
| Goggles with side sheilds and gloves |
|
|
Term
When it is neccessary to preform work in an area that has a damp or wet floor, which of the following can be done to minimize the chance or electricle shock?
A place a rubber mat on the floor
b use a wooden ladder
c wear insulated gloves
d all of the above |
|
Definition
|
|
Term
| Electrical power should always be shut off at the ______ or enterance panel and locked out in an approved manner when installing equipment |
|
Definition
|
|
Term
| A double insulated drill ________ |
|
Definition
| Generally has a plastic case with the electrical connections and motor insulated within the tool |
|
|
Term
| In electrical circuits, the ______ wire protects the operator |
|
Definition
|
|
Term
| Fires that involve ordinary materials such as paper, cardboard and wood are classified as Type ____ |
|
Definition
|
|
Term
| Fires that involve ordinary materials such as oil and gas are classified as Type __ Fires |
|
Definition
|
|
Term
Fires that involve electrical equipment are classified as Type __ Fires
|
|
Definition
|
|
Term
| Fire extinguishers that van be used on any type of fire generally contain a ______ to extinguish the fire |
|
Definition
|
|
Term
As long as the torch is kept moving below the level of the liquid refrigerent in the cylinder so as not to creat a hotspot, it is OK to heat the cylinder in this manner
T or F |
|
Definition
|
|
Term
Aluminum ladders are safe to use around electrical equipment as long as they have insulation pads on the bottom of the rungs.
T or F |
|
Definition
|
|
Term
If you are a refrigeration technician, a warm coat and gloves should be in your truck, even in the middle of the summer
T or F |
|
Definition
|
|
Term
| Oil must never be around an _____ cylinder |
|
Definition
|
|
Term
| Power tools that are not double insulated must have three-prong plugs to ensure the tool is properly ______ |
|
Definition
|
|
Term
| A way to move equipment acros a roof is to use rollers and _______ for a base |
|
Definition
|
|
Term
| Refrigerants from a refrigeration system that has a burned out motor-compressor assembly can be dangerous because it could contain a high concentration of _______ |
|
Definition
|
|
Term
Which of the following tools is different from the rest with respect to the shape of the nut or screw that it turns
a Open End Wrench
b Combination Wrench
c Hex Key
d Adjustible Wrench |
|
Definition
|
|
Term
| A socket set is an integral part of a technicians tool box because ________ |
|
Definition
Extensions allows easier acess
A rachet handle can looses and tigten nuts with minimal movement
there are multiple that can be interchanged easily |
|
|
Term
| A wireing and crimping tool is used to _______ |
|
Definition
|
|
Term
| Air conditioning and refrigeration reversable ratchet wrenches are used to |
|
Definition
| open and close refrigerant service valves |
|
|
Term
| Flare nut wrenches are used to _______ |
|
Definition
| tighten or loosen nuts on copper tubing |
|
|
Term
| Tube cutters are used to ______ |
|
Definition
|
|
Term
a guage and manifold assembly used in refrigeration work may include ______
|
|
Definition
Guage, Manifold, Valves and Hoses
Either 2, 3 or 4 Valves
|
|
|
Term
| A sling psychrometer is used to _______ |
|
Definition
| measure the dry bulb and wet bulb temperatures of air |
|
|
Term
| The halide leak detector ________ |
|
Definition
| Detects refrigerant leaks in a refrigerant system |
|
|
Term
Variable speed reversable electric drills can be used to drill holes as well as tighten and loosen screws
T or F |
|
Definition
|
|
Term
The odd shape of a Torx type screw driver is the square shaft used to tighten or loosen screws
T or F |
|
Definition
|
|
Term
A programmable charging scale measures the volume of refrigerant flow into a refrigeration system
T or F |
|
Definition
|
|
Term
An instrument called a clamp on ammeter is so called because the tongs can be clamped around a single wire.
T or F |
|
Definition
|
|
Term
| The tool used to create pipe threads on the outside of a pipe is called a ______ |
|
Definition
|
|
Term
| The tool used to create internal threads is called a _____ |
|
Definition
|
|
Term
| A ________ is used to measure the ammount of oxygen in flue products |
|
Definition
|
|
Term
| The dial-type meter used to measure the pressure in a heting unit flue pipe is called a _______ |
|
Definition
|
|
Term
| An instrument that can be used to determine the relative humidity of the air is the |
|
Definition
|
|
Term
| For what is a soldering gun used for |
|
Definition
| Soldering electrical connects and wires |
|
|
Term
| What is the major advantage of an clamp-on ammeter? |
|
Definition
| You can measure the amp pule of a compressor while it is running without having to locate both ends |
|
|
Term
| For fastening two peices of wood together the nail you would use is called the |
|
Definition
|
|
Term
| For recessing the nail for filling and finishing the wood surface the nail used would be a ______ |
|
Definition
|
|
Term
| To fasten a duct hanger strip to a floor joist, the nail used would be a _____ |
|
Definition
|
|
Term
| an outward clinch taker is used to ______ |
|
Definition
| spread the ends of a staple outward |
|
|
Term
| hollow rivits are assembled on a pin often called a ____ |
|
Definition
|
|
Term
| the hole drilled in sheet metal for tapping a screw should be the approximate size of ______ |
|
Definition
| the thread root diameter of the fastener |
|
|
Term
| in the machine screw demensions "5/16 - 18 UNC" the 5/16 indicates |
|
Definition
| the outside thread diameter |
|
|
Term
| to secure a flexable duct onto a duct collar, the best fastener would be a(n) ______ |
|
Definition
|
|
Term
Nails are sometimes coated with zinc to protect them from errosion
T or F |
|
Definition
|
|
Term
A wall anchor is a one time fastener
T or F |
|
Definition
|
|
Term
A toggle bolt is a one time fastener
T or F |
|
Definition
|
|
Term
Preforated strap is a very versitle fastener as it can be used on pipe of all sizes
T or F |
|
Definition
|
|
Term
| The easiet way to secure a thermostat cable is to use a _______ |
|
Definition
|
|
Term
| to secure two pieces of sheet metal together, a technician may use a __________ screw since no pre-drilling is required |
|
Definition
|
|
Term
| A sheet metal screw that does not require a pre-drilled recieving hole is called ________ |
|
Definition
|
|
Term
| Wood screws come in three type heads, Flat, Round, and ________ |
|
Definition
|
|
Term
| What are two types of sheet metal screws? |
|
Definition
| Tapping and Self Drilling |
|
|
Term
| What is the Largest diameter wood screw, a No 8 or No 10? |
|
Definition
|
|
Term
| if a technician needed 5/8" ACR for an installation and was located near onlu a plumbing supply store, what size and type of pipe should be asked for? |
|
Definition
|
|
Term
| the size indicated for the diameter of copper tubing used for plubming is the approximate _______ |
|
Definition
|
|
Term
| the size indicated for the diameter of ACR copper tubing is the approximate |
|
Definition
|
|
Term
| The maximum temperature at which soft soldering is done at is ______ |
|
Definition
|
|
Term
| Filler materials used in the high temperature connection of copper joints are composed of _____ |
|
Definition
|
|
Term
| when soldering or brazing the solder is ______ |
|
Definition
| melted by heat from the tubing and fitting |
|
|
Term
| molten solder flows between the two base metals being soldered because of |
|
Definition
|
|
Term
| The proper type of flame from an oxyacetylene torch used for silver braising is |
|
Definition
|
|
Term
| when soldering why should flux be used? |
|
Definition
it helps prevent oxidation
it helps keep pipes clean
it helps solder flow easier |
|
|
Term
| for cleaning ACR copper tubing before soldering, a material that can be used is |
|
Definition
|
|
Term
| Pipe threads are standardized byt the ANS, what does ANS stand for? |
|
Definition
| American National Standard |
|
|
Term
| Pipe threads, when used on pip that will contain liquid or vapor under presure, have what three charectaristics? |
|
Definition
are tapered
should at least have 7 perfect threads
generally have a V shape |
|
|
Term
| when joining steel pipe a _________ should be applied to the threads before connecting |
|
Definition
|
|
Term
L type copper is considered medium weight and is used most frequently
T or F |
|
Definition
|
|
Term
when istalling a refridgeration system, the piping should be connected with as few joints as possible
T or F |
|
Definition
|
|
Term
when soldering the technician should heat the solder with the torch to allow it to melt
T or F |
|
Definition
|
|
Term
| Copper tubing used in the feild piping of refigeration is type _______ |
|
Definition
|
|
Term
| one reason for insulation on a suction line is to help maintain proper _________ |
|
Definition
|
|
Term
| In the thread specification NPT stands for |
|
Definition
|
|
Term
| the best method of leak detection is when the refrigeration system is _______ |
|
Definition
| standing with dry nitrogen pressure of 150 PSIG in the system |
|
|
Term
| Non condensable gasses are |
|
Definition
| undesirable in a refrigeration system |
|
|
Term
| to pull a vacuum means to _______ |
|
Definition
| lower the pressure in a refrigeration system below atmoshperic |
|
|
Term
| a micron guage is used to measure _______ |
|
Definition
| absolute pressures below 1mm Hg |
|
|
Term
Which of the following represents the lowest vacuum?
A 10psia
B 5" Hg VAC
C 5 psig
D 1000 Microns |
|
Definition
|
|
Term
| Multiple evacuation means that ________ |
|
Definition
| you pull a vacuum on a refrigeration system more than once, allowing refrigerant or nitrogen into the system between each procedure |
|
|
Term
| moisture in a liquid state must be ______ before it can be removed with a vacuum pump |
|
Definition
|
|
Term
| to insure accurate testing, the best material to use for connecting lines to the vacuum pump and guage set is ______ |
|
Definition
|
|
Term
The maximum recommended pressure is 150psig on the low-side of the system
T or F |
|
Definition
|
|
Term
air entering a refrigerant system can eventually lead to compresser failure
T or F |
|
Definition
|
|
Term
Clearance tolerances are such that the ordinary clean refridgerant oil can be used satisfactorily in a vacuum pump
T or F |
|
Definition
|
|
Term
The oil in a vacuum pump should be changed after each time it is used
T or F |
|
Definition
|
|
Term
while under a deep vacuum any liquid water under the oil in the motor compressor asembly can be removed by operating the compressor motor for several seconds without any adverse effect on the system
T or F |
|
Definition
|
|
Term
after repairing a system that has had an electrical motor failure it is good feild practice to reuse the recovered refrigerent
T or F |
|
Definition
|
|
Term
| When using a standing pressure test for leak checking, _________ should never be used since an explosive mixture can be created |
|
Definition
|
|
Term
| Sludge is produced when moisture, acid and ______ are present in a system |
|
Definition
|
|
Term
| only two substances should be in the refrigeration system for proper operation. They are ______ and oil |
|
Definition
|
|
Term
| a ___ pressure could also mean refirgerent vapor is still seeping from the refrigerent system |
|
Definition
|
|
Term
| a pressure of 100 microns has been reached with the vacuum pump operating. the pump is turned off and the guage reading rises above 5000 microns and keeps rising. What does this indicate? |
|
Definition
| There may be a leak or moisture may still be present |
|
|
Term
| why is it a good idea to remove schrader stems from service valves prior to evacuation? |
|
Definition
| Schrader stems slow the evacuation process by restricting the flow |
|
|
Term
| Charging a refrigeration sytems refers to ______ |
|
Definition
| adding a refrigerant to a system |
|
|
Term
| refridgerant in vapor form is normally put into the |
|
Definition
|
|
Term
| when charging a system with vapor refrigerent from a refrigerent cylinder, the cylinder will become |
|
Definition
|
|
Term
| refrigerant in liquid form is normally put into the system through the |
|
Definition
|
|
Term
| when charging liquid refrigerant from a single valve supply cylinder the cylinder is place ______ |
|
Definition
|
|
Term
| a graduated cylinder charging device is a device that |
|
Definition
measures refrigerent by volume
has a compensation dial for adjusting the temp or refrigerent
often has a heater to keep te refrigerent temp from dropping |
|
|
Term
| if a critically charged refrigeration system is overcharged what will likley result? |
|
Definition
| Increased operating pressures |
|
|
Term
| fractionation occures when _____ |
|
Definition
| some of a blended refrigerent evaporates or condenses before the rest of the blend |
|
|
Term
| when charging a refrigeration system with a near-azeotropic mixture, what must be donw to prevent liquid from entering the system? |
|
Definition
| Charge as a liquid through the low side using a restrictor |
|
|
Term
when the system pressure are lower than the pressure in the refrigerant tank, such as hen the system has just been evacuated or the system is out of refrigerant, refrigerant can be added to botht he high and low sides of the system
T or F |
|
Definition
|
|
Term
if the tank is a reusable tank, there are no check valves and the system refrigerant can enter the tank as long as the system pressure is higher than the pressure in the tank
T or F |
|
Definition
|
|
Term
the quickest method to charge a system is to charge vapor only
T or F |
|
Definition
|
|
Term
a manufactures charging chart may be used when available to determine the correct charge for a system
T or F |
|
Definition
|
|
Term
| refrigerant in vapor form is affef to the system through the ____ side of the system |
|
Definition
|
|
Term
| As refrigerant vapor is removed from a supply cylinder the pressure in the supply culinder will _______ |
|
Definition
|
|
Term
| The _______ is used to help techniciancs perform a number of task including taking pressure readings on the high side of the system and trapping all of the system refrigerant in the receiver to perform system service. |
|
Definition
|
|
Term
| the charging device that holds refrigerant has a visable column of liquid and can be used to viually see the ammout of refrigerant us is call the ________ |
|
Definition
| graduated charging cylinder |
|
|
Term
| How many chlorine atomes does it take to destroy 100,000 ozone molecules in the stratusphere? |
|
Definition
|
|
Term
| The ____ takes into consideration both the direct and indirect global warming effects of refrigerents? |
|
Definition
|
|
Term
Which one of the following refrigerents is a CFC type refregerant?
R-22
R-123
R-134a
R-12 |
|
Definition
|
|
Term
| Which type of redrigerent has the highest ozone depletion potential (ODP)? |
|
Definition
|
|
Term
| The abbreviation for refrigerents containing chlorine, flourine and carbon is _____ |
|
Definition
|
|
Term
| The ozone depletion factor for R-12 is ___ |
|
Definition
|
|
Term
Which of the following is an example of an HCFC refregerent?
R-12
R-402
R-22
R-134a |
|
Definition
|
|
Term
Which of the following refrigerent is considered an HFC tyoe of refregerent?
R-134a
R-12
R-22
R-11 |
|
Definition
|
|
Term
| The abbreviation for refrigerents containing chlorine, flourine carbon and hydrogen is _____? |
|
Definition
|
|
Term
| The abreviation for refregerents containing flourine, carbon and hydrogen is ___? |
|
Definition
|
|
Term
| Refregerents that are made up of two refregerents, that when blended in the right proportions combine to make a third, stable refrigerent are called ______ |
|
Definition
|
|
Term
| To reprocess refrigerent to meet new product specifications is called |
|
Definition
|
|
Term
| To remove the refrigerent from a system without any testing or processing and to be put back into the same system is called_______ |
|
Definition
|
|
Term
A refrigerent reclaimed from a system may be charged back into the system from which it came.
T or F |
|
Definition
|
|
Term
Machanical refrigerant recovery equipment must meet specification establsihed by the 1993 ARI 740 standard.
T or F |
|
Definition
|
|
Term
When a technician works for a company in which the technician does not have a financial interest the technician does not have to be certified.
T or F |
|
Definition
|
|
Term
| HCFC based blends work best with ________ lubricants, while HFC-based blends work best with ester lubricants |
|
Definition
|
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Term
| The small ammount of refrigerant released when removing guage hoses from the system is called _________ |
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Definition
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Term
| The fastest way to remove a refrigerent from a system is with the refrigerent in a _______ state |
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Definition
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