Exam 50: Commercial Rooftop, Packaged, Variable Refrigerant Flow, and Variable Air Volume Systems

The curb's cross braces are intended to support the duct connections to the unit, but not the entire air distribution system.

With both fists in front of the body, pointing the thumbs outward tell the crane operator to ____ the boom.

Name the four common types of VAV boxes.

When multiple rooftop units are used to condition the air in a building, it is common practice to label the units and their corresponding ____________________.

Improper clearances do not affect the ability of service personnel to perform their jobs adequately.

Gasketing materials and foam panels that are shipped with the curb are not part of the curb and should be discarded.

A frame that is used to mount HVAC equipment is called a(n) ____________________.

Be sure to provide proper and adequate support for the duct system according to ____.

Rooftop units are often positioned ____ the space that is to be served by the equipment.

In order to deliver different volumes of air to various areas in an occupied space, the blowers used on VAV systems must be able to modulate their openings to accommodate the changing needs of the system.

Package units are factory-assembled, factory-charged, self-contained systems that have all of the major system components contained in a single housing.

By raising the forearm in the air, index finger pointing upward and holding the hands straight, the operator will know to raise the cable on the crane.

It should be noted that, in most cases, the supply and return ductwork must be attached to the ____ before the unit is set in place.

Curbs can be prefabricated, but many larger curbs are shipped unassembled.

An enthalpy sensor includes solid state temperature and ____ sensors.

The fans that move air through the air-cooled condensers are of the ____-type.

Explain the term "free cooling."

The temperature sensor used in chilled-water VAV systems to detect when the outside air is cold enough to cause freezing, is typically called a(n) ____________________.

It is good field practice to double-check and possibly triple-check the ____ decision, since the cost of repairing an improperly cut roof can be very high.

What are some drawbacks of adding more antifreeze than needed to prevent freezing in the chilled water piping system?