The size indicated for the diameter of ACR copper tubing is the ___.

The maximum temperature at which soft soldering is done is ___.

Brazing is done at ___ soldering.

When soldering or brazing, the solder is ____.

Molten solder flows between the two base metals being soldered because ____.

K-type copper is heavy-duty with a thick tubing wall.

L-type copper is considered medium weight and is used most frequently.

M is a lightweight copper and is not commonly used in our industry.

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.

When installing a refrigeration system, the piping should be connected with as few joints as possible.

When soldering, the technician should heat the solder with the torch to allow it to melt.

An air-acetylene unit usually consists of a B tank of acetylene gas, a regulator, a hose, and a torch.

ABS and PVC pipe can be used to carry the new blended refrigerants in low temperature applications.

When making a swage joint, what should the depth of the enlarged portion of the tube be?

The best method of leak checking is when the refrigeration system is ____.

When moisture is present in a refrigeration system, it will react with the refrigerant and the oil to form ____.

Non-condensable gases ____.

To pull a vacuum means to ____.

A compound gauge ____.

A micron gauge is used to measure ____.

At what pressure range does the technician valve off the vacuum pump when evacuating to a deep vacuum?

Which of the following represents the lowest vacuum?

A multiple evacuation means that ____.

Moisture in a liquid state must be ______ before it can be removed with a vacuum pump.

To ensure accurate testing, the best material to use for connecting lines to the vacuum pump and gauge set is ____.

The maximum recommended pressure for leak testing is 150 psig on the low-pressure side of the system.

Air entering a refrigerant system can eventually lead to compressor failure.

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.

After repairing a system that has had an electrical motor failure (compressor burnout), it is good field practice to re-use the recovered refrigerant in that system.

Why is refrigerant not used for a system standing pressure test?

Why is nitrogen considered a "non-condensable gas"?

A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises to 500 microns and stays there. What does this indicate?

A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises to 5,000 microns and stays there. What does this indicate?

A pressure of 100 microns has been reached with the vacuum pump operating. The pump is turned off and the gauge reading rises above 5,000 microns and keeps rising. What does this indicate?

How many chlorine atoms does it take to destroy 100,000 ozone molecules in the stratosphere?

The ______ takes into consideration both the direct and indirect global warming effects of refrigerants.

Which of the following refrigerants is a CFC-type refrigerant?

Which type of refrigerant has the highest Ozone Depletion Potential (ODP)?

The abbreviation for refrigerants containing chlorine, fluorine, and carbon is ____.

As of July 1, 1992, it is illegal to intentionally vent ____ refrigerants into the atmosphere.

Which of the following is an example of an HCFC refrigerant?

Which of the following refrigerants is considered an HFC-type of refrigerant?

The abbreviation for refrigerants containing chlorine, fluorine, carbon, and hydrogen is ____.

The abbreviation for refrigerants containing fluorine, carbon, and hydrogen is ____.

Refrigerants that are made up of two or more liquids are called ____.

To process refrigerant to new product specifications is called ____.

To clean refrigerant by the use of filter dryers is called ____.

To remove the refrigerant from a system without any testing or processing and to be put back into the same system is called ____.

Refrigerants that have a low Ozone Depletion Potential (ODP) will, in turn, have a high "Total Equivalent Warming Impact" (TEWI).

A refrigerant reclaimed from a system may be charged back into the system from which it came.

The DOT-approved cylinder used for recovering refrigerant is gray and yellow.

Mechanical refrigerant recovery equipment must meet specifications established by the 1993 AHRI 740 standard.

Refrigerants that damage the ozone layer contain an element called ________.

The trapping of the Earth's heat in the atmosphere which is causing global warming is called the greenhouse effect.

Production of CFC refrigerants became illegal on January 1, ________.

The small amount of refrigerant released when removing gauge hoses from the system is called ________.

The DOT-approved cylinder in which refrigerant may be recovered has a mechanism for shutting the recovery system off when it reaches approximately ________% full.

The fastest way to remove refrigerant from a system is to take it out in the ________ state.

Why is stratospheric ozone so important to our environment?

When did it become illegal to "intentionally" vent CFC refrigerants to the atmosphere? Give the month, day, and year.

When did it become illegal to "intentionally" vent HFC refrigerants to the atmosphere? Give the month, day, and year.

How are near-azeotropic blends identified?

On what does universal EPA certification allow a service technician to work?

Charging a refrigeration system refers to ____.

Refrigerant in vapor form is normally put into the system through the ____.

When charging a system with vapor refrigerant from a refrigerant cylinder, the cylinder will become ____.

Refrigerant in liquid form is normally put into the system through the ____.

When charging liquid refrigerant from a single valve supply cylinder, the cylinder is placed ____.

A graduated cylinder charging device is a device that ____.

If 22 oz. of refrigerant are to be added to a refrigeration system and the supply cylinder weighs 24 lb. 12 oz. before any is added, what will be the supply cylinder weight after the system has been charged?

If 30 oz. of refrigerant are to be added to a refrigeration system and the supply cylinder weighs 26 lb. 4 oz. before any is added, what will the supply cylinder weigh after the system has been charged?

If a critically charged refrigeration system is overcharged, which of the following is a likely result?

Fractionation occurs when ____.

When charging a refrigeration system with a near-azeotropic mixture, what must be done to prevent liquid from entering the system?

When adding refrigerant in vapor form to an operating refrigeration system, the refrigerant must be added to the low-pressure side of the system.

When the system pressures are lower than the pressure in the refrigerant tank, such as when the system has just been evacuated or if the system is out of refrigerant, refrigerant can be added to both the high- and low-pressure sides of the system.

If the tank is a reusable tank, there are no check valves and system refrigerant can enter the tank as long as the system pressure is higher than the pressure in the tank.

The quickest method to charge a system is to charge only vapor.

When adding refrigerant in liquid form into the high-side of the system, the system motor/compressor assembly is running.

Using a restrictor, liquid refrigerant can be charged into the low-side of the system with the system operating.

One good feature of an electronic charging scale is that it counts upward as refrigerant is removed, to tell the technician how much refrigerant was used.

A manufacturer's charging chart may be used when available to determine the correct charge for a system.

Glide is the range of temperatures/pressures in which a blended refrigerant will condense.

If the pressure in the refrigerant cylinder drops down too low to charge a system (cylinder pressure = low side system pressure), how can the technician increase the cylinder pressure?