CDCP Cooling and Environmental Control 5

Question 1

What is the main advantage of a waterside economizer over an airside economizer in a data center?

Accepted Answer

It does not introduce outside contaminants into the data center

Answer

Waterside economizers cool water via a cooling tower or dry cooler and then use that water in the chiller loop, keeping outside air out of the IT space.

Question 2

A data center manager notices the return air temperature to the CRAC units is unusually low. What does this most likely indicate?

Accepted Answer

Excessive cold air bypass (short-cycling)

Answer

Low return air temperature indicates cold supply air is bypassing IT equipment and returning directly to the cooling unit without absorbing heat.

Question 3

In immersion cooling for data centers, what fluid is typically used to submerge IT equipment?

Accepted Answer

Dielectric fluid

Answer

Dielectric (electrically non-conductive) fluids are used in immersion cooling so the liquid can safely contact live electronic components.

Question 4

What is the effect of raising the cold aisle temperature set point from 65°F to 75°F in a modern data center with ASHRAE A1-rated equipment?

Accepted Answer

Chiller efficiency improves, reducing energy consumption

Answer

A higher cold aisle set point allows chillers to operate at warmer chilled water temperatures, which significantly improves chiller COP and saves energy.

Question 5

Which organization publishes the widely adopted thermal guidelines (A1–A4 classes) for data center IT equipment?

Accepted Answer

ASHRAE

Answer

ASHRAE's Technical Committee 9.9 publishes the thermal guidelines, including the A1–A4 equipment classes used globally.

CDCP - Certified Data Centre Professional Practice Test

CDCP - Certified Data Centre Professional Practice Test

CDCP Cooling and Environmental Control 5