Building Engineering HVAC and Building Mechanical Systems

Question 1

What does ASHRAE Standard 62.1 govern in building design?

Accepted Answer

Ventilation for acceptable indoor air quality

Answer

ASHRAE 62.1 establishes minimum ventilation rates and IAQ requirements for commercial and institutional buildings.

Question 2

What refrigerant is widely used in commercial HVAC systems as a replacement for R-22?

Accepted Answer

R-410A

Answer

R-410A became the dominant replacement for R-22 in commercial split systems after the phase-out of ozone-depleting CFC and HCFC refrigerants.

Question 3

What is the primary function of a Variable Air Volume (VAV) box in an HVAC system?

Accepted Answer

To modulate the volume of conditioned air delivered to a zone

Answer

A VAV box uses a damper and controller to vary airflow to each zone in response to thermostat demand, saving fan energy compared to constant volume systems.

Question 4

Which heat transfer fluid is commonly circulated through chilled water HVAC systems?

Accepted Answer

Chilled water at 40–45°F

Answer

Chilled water systems circulate water cooled to 40–45°F from a central chiller to air handling units where it absorbs heat from return air.

Question 5

What is the purpose of an economizer in an HVAC air handling unit?

Accepted Answer

To use outdoor air for free cooling when conditions are favorable

Answer

An air-side economizer opens dampers to bring in cool outdoor air instead of running mechanical cooling, reducing energy consumption significantly.

Building Engineering Practice Test

Building Engineering Practice Test

Building Engineering HVAC and Building Mechanical Systems