Chapter 8 Air Handling Equipment and Sales
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Which of the following finishes would be appropriate for an outdoor air handling unit? Select all
that apply.
1) _______
A) Aluminum. B) Simply painted.
C) Galvanized. D) Galvanized and painted.
2) What are the normal materials of construction for coils? 2) _______
A) Copper tubes and aluminum fins. B) Copper tubes and fins.
C) Aluminum tubes and copper fins. D) Steel tubes and aluminum fins.
3) Which is normal flow in a cooling coil? 3) _______
A) Crossflow, which is water in on the entering air side.
B) Counterflow, which is water in on the leaving air side.
C) Crossflow, which is water in on the leaving air side.
D) Counterflow, which is water in on the entering air side.
4) What might happen if the air velocity through a cooling coil is too high? Select all that apply. 4) _______
A) Water will be carried off the coil. B) Fins will flutter and cause noise.
C) Pressure drop will be excessive. D) Fins will erode due to dust
impingement.
5) Which statements are true regarding coil face velocities? Select all that apply. 5) _______
A) Heating coils generally have same face velocity as cooling coils in the same unit.
B) Cooling coil face velocities can be increased if they have more rows.
C) Heating coil face velocities can be up to 1200 fpm.
D) Cooling coil face velocities can be up to 600 fpm, but lower velocities are preferred.
6) Which statement is true about electric heating coils? 6) _______
A) Capacity control can be achieved by relays or by the use of face and bypass dampers.
B) Electric coils have high pressure drops due to the density of the heating elements.
C) Electric coils can have higher face velocities than hydronic coils.
7) Which statement is true about refrigerant cooling coils? 7) _______
A) Control is achieved by a valve on the discharge of the coil.
B) Refrigerant changes from liquid to gas in the coil.
C) Face velocity can be high since refrigerant coils operate dry.
D) Refrigerant changes from gas to liquid in the coil.
8) Filters are rated based on which of the following systems? 8) _______
A) Retention ratio value. B) HEPA rating value.
C) Material holding value. D) MERV rating value.
9) Which of these would be considered a high efficiency filter for use in a clean room or healthcare
facility? Select all that apply.
9) _______
A) Electrostatic precipitator. B) HEPA filter.
C) ULPA filter. D) Bag filter with throw-away prefilter.
10) Which of these filters might be used for odor removal? Select all that apply. 10)
______
A) Potassium permanganate. B) Iron impregnated charcoal.
C) Activated charcoal. D) Sodium hydroxide.
11) Which of the following is the most appropriate method to prevent over-pressurization of a large
building with high pressure drop return air duct?
11)
______
A) Return fan. B) Relief fans.
C) Gravity dampers. D) Motor-operated dampers.
12) Which of the following fans would be appropriate for kitchen grease exhaust? 12)
______
A) Horizontal blast utility set. B) Upblast roof ventilator.
C) Upblast axial fan. D) Down blast roof ventilator.
13) Which of the following is not a centrifugal fan design? 13)
______
A) Axial fan. B) Utility set. C) Fan array. D) Roof ventilator.
14) Propeller fans are used in which application? 14)
______
A) Low pressure high flow. B) High pressure low flow.
C) High pressure high flow. D) Low pressure low flow.
15) Which are advantages of fan arrays? Select all that apply. 15)
______
A) They operate at lower speed.
B) They are compact in length.
C) They offer redundancy.
16) For a given duct system, if the fan is slowed by 50%, the airflow will decrease by 50%. What will
happen to the system pressure drop? Power?
16)
______
A) Pressure drop will be 25%; power will be 12.5%.
B) Pressure drop will be 50%; power will be 25%.
C) Pressure drop will be 50%; power will be 50%.
17) Which is the most likely construction for low velocity ductwork? 17)
______
A) Rectangular with internal insulation. B) Flat oval with internal insulation.
C) Flat oval with external insulation. D) Rectangular with external insulation.
18) Which is the most likely construction for medium velocity ductwork? 18)
______
A) Rectangular with internal insulation. B) Flat oval with internal insulation.
C) Flat oval with external insulation. D) Rectangular with external insulation.
19) Ceiling diffuser performance relies on a phenomenon called the Coanda effect. What is it? 19)
______
A) Cold air clings to the ceiling upon being discharged.
B) Cold air diffuses to achieve even space temperatures.
C) Cold air swirls to mix with room air.
D) Cold air is directed downward to sources of heat gain.
20) Which of these diffuser types cope well with varying airflow, as in a VAV system? Select all that
apply.
20)
______
A) Louvered face. B) Perforated-face. C) Linear-slot.
21) Which statement is true about displacement ventilation? 21)
______
A) Air from the floor is prone to carrying dust.
B) Mixing is enhanced resulting in even air temperatures.
C) Supply air temperatures are lower than for overhead systems.
D) Vertical airflow may have health benefits.
22) Which heat recovery system will result in the highest cooling savings? 22)
______
A) Heat wheel. B) Runaround. C) Heat pipe. D) Plate.
23) Which heat recovery system has the least hazard of recirculating exhaust into the ventilation air? 23)
______
A) Heat pipe. B) Plate. C) Heat wheel. D) Runaround.