HVAC Residential vs Commercial HVAC 3

Question 1

Which refrigerant has been the standard for new residential split systems since R-22 was phased out?

Accepted Answer

R-410A

Answer

R-410A replaced R-22 as the standard residential refrigerant after the EPA phased out R-22 production due to its ozone-depleting properties.

Question 2

A Building Automation System (BAS) is more commonly found in commercial buildings than residential because:

Accepted Answer

Commercial buildings have multiple HVAC zones and systems requiring centralized control

Answer

BAS integrates control of multiple HVAC systems, lighting, and other building systems across many zones, which is impractical to manage manually in large commercial buildings.

Question 3

Economizer cycles are more commonly implemented in commercial HVAC systems because they:

Accepted Answer

Use outdoor air for 'free cooling' when conditions allow, saving energy in large systems

Answer

Economizers use outdoor air when it's cool enough to provide free cooling, and the energy savings justify the cost in large commercial systems.

Question 4

What is a dedicated outdoor air system (DOAS) primarily designed to handle?

Accepted Answer

Ventilation and dehumidification of outdoor air separate from sensible cooling

Answer

DOAS systems handle 100% outdoor air for ventilation and latent (moisture) loads, allowing other equipment to handle sensible cooling more efficiently.

Question 5

In commercial buildings, ASHRAE Standard 62.1 governs:

Accepted Answer

Ventilation rates for acceptable indoor air quality

Answer

ASHRAE 62.1 sets minimum ventilation rates for commercial buildings to ensure acceptable indoor air quality for occupants.

HVAC - Heating, Ventilation, and Air Conditioning Practice Test

HVAC - Heating, Ventilation, and Air Conditioning Practice Test

HVAC Residential vs Commercial HVAC 3