Chapter 7

Question 1

The air blower used in a forced warm air furnace is usually driven by
A. An electric motor geared directly to the blower rotor
B. A small diesel engine via a V-belt connected to a fixed pulley mounted on the blower shaft
C. A small internal combustion engine geared directly to the blower rotor
D. An electric motor via a V-belt connected to a fixed pulley mounted on the blower shaft

Answer 1

D

Question 2

Which of the following are types of air distribution systems?
A. Extended plenum
B. Perimeter loop
C. Perimeter radial
D. All of the above

Answer 2

D

Question 3

To determine the tension in a blower’s driving belt, a force of about ____ should be applied.
A. 25N (5.6 lbf)
B. 30N (6.7 lbf)
C. 45N (10 lbf)
D. 75N (17 lbf)

Answer 3

C

Question 4

In the warm air supply, temperature is more than blank higher than the return air temperature. The air filters are possibly plugged.
A. 25°C, [45°F]
B. 38°C, [68°F]
C. 50°C, [90°F]
D. 65°C, [117°F]

Answer 4

B