Research on Air Conditioning in Buildings

What is the primary function of an air conditioning (AC) system?

• To heat a building

• To cool a building

• To control the humidity of the air

• All of the above

Why is air conditioning provided in buildings?

• To maintain an environment conducive to the health and wellbeing of the inhabitants

• To increase the oxygen levels to dangerous levels

• To make the air dry and uncomfortable

• To add more CO2 and odours to the air

What does 'conditioned' air supply?

• Excessive oxygen

• Adequate oxygen, comfortable temperature, and removal of CO2 and odours

• High levels of CO2 and odours

• Only heating

In central plant AC systems, how is the air conditioned before being distributed?

• By individual room units

• By a central unit before distribution via ducting

• By portable air conditioners

• By window air conditioners

What is the effect of conditioning air in central plant AC systems?

• The effect will vary in different parts of the building

• The effect will be identical throughout the building

• The effect will be stronger near the central unit

• The effect will be weaker near the central unit

How can the effect of air conditioning be changed in central plant AC systems?

• By adjusting the room thermostat

• By changing the off-coil temperature

• By opening windows

• By using fans

What is the purpose of the preheater battery in the winter cycle?

• To cool the air to 7ºC

• To mix room air with fresh air

• To heat fresh air to 7ºC and prevent filters from freezing

• To dehumidify the air

What percentage of room air can be mixed with fresh air using the recirculation duct?

• 10%

• 25%

• 50%

• 75%

What is the 'duty' of a supply fan?

• The temperature of the air it cools

• The volume and static pressure of the air it operates

• The percentage of fresh air it mixes

• The amount of moisture it removes

How is air cooled in the cooling coil?

• By heating it to 34ºC

• By mixing it with fresh air

• Using chilled water or a refrigerant gas

• By increasing the static pressure