Exam 12: Ventilating, Air Conditioning, and Other Facilities

Whenever the specific area is cooled to the desired temperature, a(n) __________opens the control circuit to the motor controller and the air movement stops until the area again requires cooling.

When hermetic refrigerant motor-compressors are designed to operate continuously at currents greater than 156 percent of the rated-load current, the nameplate is marked with __________current.

What is the maximum deflection force in pounds for a belt in the cross-section class D?

The main parts of a precipitator are the__________ , collector cells, and power supply.

What overload protection is required for the motors of the fan coil units in the cooling equipment?

Low-pressure refrigerant flows through the __________to provide cooling for the motor of a hermetically sealed compressor.

The exhaust blower unit consists of a three-horsepower, three-phase, 208-volt motor driving a propeller-type fan through a(n) __________drive.

The__________ protective device is determined by multiplying the rated-load current, or the branch-circuit selection current of the hermetic refrigerant motor-compressor, by 225 percent and then adding all concurrent loads such as electric heaters, motors, and so on.

The __________current is determined by the manufacturer of the hermetic refrigerant motor compressor by testing at rated refrigerant pressure, temperature conditions, and voltage.

One method of removing oil mist is by the use of__________ units.

In the precipitator, wires made of which metal give the particles a positive charge?

The manufacturer determines the__________ by multiplying the rated-load current, or the branch-circuit selection current of the hermetic refrigerant motor-compressor, by 125 percent.

What precautions must be taken when installing drive belts?

A(n)__________ converts high-voltage ac into high-voltage dc.

How are pollutants actually trapped by the precipitator?

In most instances, the rated-load current is at least equal to 64.1 percent of the hermetic refrigerant motor- compressor's __________current.

The correct tension for a belt in the cooling unit drive can be determined from the __________.

What is the basic construction of a precipitation unit?

The current draw of a precipitator is __________.

What is oil mist and why is it detrimental?