The EPR valve is installed in the suction line at the evaporator outlet and it ____.

EPR valves are also referred to as ____ valves.

To protect the compressor during periods of hot pull down, a(n) ____ valve is used.

The refrigeration compressor motor can be operated at about ____% over its rated capacity without harm during the pulldown.

Refrigeration systems are designed to operate year round. For this reason they are equipped with ____.

Which of the following is a type of low-ambient temperature head pressure control?

Which of the following is another type of low-ambient temperature head pressure control?

Frequently on smaller condensing units, one fan will run continuously and the other fan will be cycled on and off with a(n) ____.

____ are snap-acting valves that open and close very fast when the electrical energy is applied to the coil.

When a system pumps down, where is the refrigerant stored?

Random defrost is accomplished ____.

Defrost using internal heat is accomplished using ____.

How does the receiver ensure that only 100% liquid refrigerant enters the liquid line?

The normal position for a suction service valve during normal operation is ____.

Two-temperature operation is desirable when more than one evaporator is used with a compressor.

The crankcase pressure regulator (CPR) puts a limit on the pressure that can return to the compressor.

A suction line accumulator is used to ensure that liquid refrigerant enters the compressor.

Oil separators work on the principle of low refrigerant and oil velocity.

Oil separators are used to remove oil from the refrigerant.

Automatic pumpdown systems are equipped with a(n) ____________________ to prevent refrigerant from reaching the evaporator.

The ____________________ is a mechanical control that keeps the refrigerant pressure in the evaporator from going below a predetermined point.

Two types of relief valves are the spring-loaded valve and the ____________________ valve.

The spring-loaded type of relief valve is normally brass with a(n) ____________________ seat.

To protect a refrigeration compressor when refrigerant loss occurs, a(n) ____________________ control is used.

The two forces that control the EPR valve are:

The oil pressure safety control is prevented from de-energizing a compressor immediately after start-up because:

Where is the refrigerant filter drier found?

Where is the refrigerant sight glass normally located?

List four causes of liquid floodback.

In a kitchen, ____ condensing units may be easier to maintain.

The three-way heat reclaim valves in most heat reclaim systems are ____ operated.

The heat reclaim valve is a three-way valve that is activated by a solenoid operated by a ____.

When a parallel heat reclaim system is used, the heat reclaim condenser must be sized to handle ____% of the refrigeration system’s rejected heat when in the heat reclaim mode.

Heaters that are made with resistance-type wire run just under the surface of the cabinet are called ____ heaters.

Knock-down walk-in coolers are constructed of interlocking panels from ____ thick.

In condensate removal, the drain lines should be sloped downward about ____ in. per foot for proper drainage.

The precharged tubing used for installing refrigeration piping is called a ____.

One of the advantages of parallel compressor systems is ____.

The most popular secondary fluid currently used in refrigeration systems is ____.

One of the disadvantages of the secondary-fluid refrigeration systems is ____.

At its triple point, CO₂ can exist as ____.

Refrigerated compressed air driers typically run ____% of the time.

The primary advantage of parallel compressor systems is their ____.

The air used for “pneumatic controls” must be ____.

When purchase cost alone is considered in selecting refrigeration equipment, the equipment may not perform acceptably.

An open case is more efficient than a closed case.

Self-contained equipment normally plugs into either a 120-V or 230-V electrical outlet.

Often, parallel compressor systems employ a satellite or booster compressor.

Carbon dioxide (CO₂) is one of the newest refrigerants.

CO₂, ammonia, propane, butane, and isobutane are all natural refrigerants.

Distributed supermarket refrigeration modules that are located very close to the display cases they refrigerate are becoming increasingly popular.

Refrigerated air driers are normally self-contained refrigeration systems that may be air cooled or water cooled.

Retail stores use ____________________ refrigeration units for merchandising their products.

When the inside of the evaporator cabinet is below freezing, heat has to be provided to keep the condensate in the line ____________________.

The precharged tubing for refrigeration piping is ____________________ at both ends and has quick connect fittings.

____________________ are basically refrigeration systems located in the air supply, after the storage tank.

A condensing unit can be located:

Pilot operation means that the valve uses the refrigeration system’s pressures to move a sliding mechanism when its solenoid is energized.

The two alternative means of disposing of the condensate that is gathered on the evaporator of all refrigeration equipment are:

The hot gas bypass valve in a refrigerated air drier is called a pressure regulator because:

Tremendous forces that can cause refrigerant lines and values to rupture

When air is used for controls

Package ice machines store their own ice at ____°F in a bin below the ice maker.

Most package ice makers are ____-cooled.

____ ice is normally made in a vertical refrigerated cylinder surrounded by the evaporator on the outside.

The auger in a flake ice maker has cutting surfaces called ____.

A ____ is used to turn the auger in a flake ice machine.

Most ice flakers have a ____ that reduces the auger drive motor’s speed from about 1725 rpm to 9 to 16 rpm.

____ evaporators have ice cups designed to cause the ice to fall out of the cups during defrost.

____ ice cube machines usually have vertical evaporator plates with water flowing over the individual cells.

_____ between the evaporator cells allow air entering from the edges of the ice to travel along the entire ice slab and relieve the suction force.

_____ are simply small computers that contain stored programs or algorithms.

For maximum efficiency, individual ice machine models have different programs called algorithms stored in their _____

Microprocessors are often referred to as _____

Many filter manufacturers use ____ to inhibit calcium or lime scale buildup.

Most package ice machines are designed to be located in ambient temperatures of _____

When using cleaning and sanitizing chemicals, it is unnecessary to wear protective clothing and eyewear.

Ice-making machines are the same as ice-holding machines such as those seen on the outside of a convenience store or service station.

The gear motor assembly is less prone to failure than any other part in the ice flaker.

Manufacturers of ice flakers install thermal overload controls in the motor windings or a manual-reset, current-type overload control.

It is important that the auger does not wobble within the freezing cylinder or evaporator.

Water levels can be sensed and controlled by a probe located in the water reservoir.

Solid forms of ice last longer because there is more weight with less surface area.

Most ice makers use a hot gas harvest or defrost to melt an ice sheet off the evaporator.

Ice is not considered a food source.

It is recommended that at least ________________ a year, the probe should be removed from the water reservoir and cleaned.

26. ________________-type devices are usually located in the spout.

27. ________________ sense the buildup of ice by infrared technology. This control allows the ice machine to shut down before the ice chokes the spout opening.

28. ________________ controls use sound waves and vibrations, which are reflected back to the control from the ice.

Which of the following is NOT a step in installing a package machine?

Some of the methods used for ice bin control are:

List the types of devices used to control ice production in commercial ice machines.

When operating at the proper refrigerant charge, ice production in flake ice machines depends on two main factors. List these factors.

Ice production, cycle times, and system operating pressures for an air-cooled ice machine mainly depend on two factors. Identify them.