Exam 49: Operation, Maintenance, and Troubleshooting of Chilled-Water Air Conditioning Systems

The ____________________ is used in water circuits and is a quick-shutoff valve̶ as it only needs to be turned one-quarter turn from on to off, like a ball valve.

The first step in starting a chilled-water system is to ____.

The safety switch in the chilled water line that is activated by water flow is called a(n) ____________________.

Chillers manufactured in the last few years all have ____ controls.

After chemically cleaning a condenser, it is extremely important to make sure that the chemicals are neutralized or the tubes may be damaged.

After being cleaned, the condenser tubes may be checked for stress cracks, erosion, wear on the outside and other defects, by means of what type of instrument?

Reciprocating chillers have crankcase heaters to ____.

To remove particles that may be in suspension and circulating in a water circuit, a(n) ____________________ is used.

The scroll-chiller compressor needs crankcase heat and it must be energized for the length of time the manufacturer requires, usually____________________ hours.

When a water-cooled chiller is operating normally, it can usually be left unattended, except for which component?

The technician should also be aware of the ____________________ through the contactors that must be satisfied before startup.

Before allowing the compressors of a water-cooled chiller to start up, what two things must be done?

If the compressor motor megohm value begins to decrease, it is a sign that ____________________ or some other foreign matter may be getting into the system.

Low-pressure chillers operate in a vacuum and will stay in a vacuum if the equipment room is not warm enough to keep the refrigerant warm.

What may happen if a lithium-bromide absorption system is started with the cooling water too cold?

The operation of chillers involves starting, running, and stopping the system's components in an orderly manner.

A typical chilled water system is designed to operate with a leaving water temperature of ____°F.

Centrifugal chillers range in size from ____ tons for a single chiller.

If the purge unit on a chiller is operating very frequently, the system may have a leak.

If an absorption unit is started with very cold water in the cooling tower, the lithium bromide in the unit may ____________________.