Exam 1 HVAC

Which of the following is the air temperature of the air flowing through the ductwork of a comfort control system while its in the cooling mode?

55 degrees F

The fans that you see on a roof-top chiller are used to cool the

Condensers

One of the most efficient forms of air filtering equipment is the

Electrostatic Air-Cleaning System. One of the most efficient air-cleaning systems is the electrostatic air-cleaning system.

The type of chiller that uses a screw-type impeller is the

Centrifugal Chiller Pg. 23, 24

The type of sensor that measures humidity is the

Humidistat Pg. 11 and 31

One ton of air conditioning is equal to how many BTU?

12,000 BTU: British Thermal Unit, which is the amount of heat that will raise or lower one pound of water one degree Fahrenheit. Ton: Atonofair conditioningor refrigerationisequal to12,000 BTU. A small home air conditioner can be as small as 5,000 BTU, and a large commercial system can be in the thousands of tons. Pg. 6

If water is contained in a closed vessel having absolute pressure of 0.15 psia, such as in the evaporator area of the absorption generator, the water will boil at

40 degrees F Pg. 19

A system that uses heat to create chilled water is called a(n)

Absorption Systems Check Pg. 18

The building supervisor is connected directly to the chiller and also to the

Air Terminal Manager Pg. 29 An interface module called a terminal system manager (TSM) is connected between the terminals and the chiller and the building supervisor computer. The building supervisor communicates to the air terminals via a terminal system

The heating capacity of a heat pump at 47° F and 17° F is measured by a rating called

COP: Coefficient of Performance is a term used to rate a heat pump at 47°F and 17°F on its heating capacity. Pg. 6

A system that cools the air by spraying water into a tower is called

Evaporative Cooling Pg. 22

The device in a refrigeration system that causes the refrigerant to go from a liquid to a gas is the

Evaporator Pg. 16, 22

The material that's used in anabsorption-type chiller is

Lithium Bromide Pg. 19

The newer refrigerant in use today is

R-134a Pg. 23

What component allows a heat pump to switch between heating and cooling modes of operation?

Transfer valve