Chapter 130

Question 0

The purpose of a vacuum breaker used with steam coils is to:
A) ensure positive air pressure in the conditioned space
B) ensure negative air pressure in the conditioned space
C) prevent excessive temperatures within the steam coil
D) prevent possible freezing caused by a vacuum or negative pressure in the steam coil
E) ensure proper operation of the steam control valve

Answer 0

D) prevent possible freezing caused by a vacuum or negative pressure in the steam coil

Question 1

The purpose of the flow switch or sail switch is used with hot water coils is to:
A) stop the fan and close the outside air dampers if the low limit temperature controller malfunctions or the heat source fails
B) open the outside air dampers wide when the outside air temperature rises
C) increase the heat source temperature if the outside air temperature creases
D) close the outside air dampers and stop the fan if the flow of water is interrupted due to pump failure or closing of the hand valves
E) increase the hot water flow through the coil if the outside air temperature is too low

Answer 1

D) close the outside air dampers and stop the fan if the flow of water is interrupted due to pump failure or closing of the hand valves

Question 2

Which of the following steam traps are preferred for use with steam coils operating at low and medium steam pressure?
A) inverted bucket
B) dynamic
C) f & t trap (float and thermostatic)
D) thermostatic only

Answer 2

C) f & t trap (float and thermostatic)

Question 3

The inverted bucket trap is used when the steam pressure is:
A) lower than 175 kPa
B) higher than 172 kPa
C) higher than 300 kPa
D) lower than 200 kPa

Answer 3

B) higher than 172 kPa

Question 4

A modulating valve can be used for a steam coil when the air inlet temperature is below 1.5*C
A) true
B) false

Answer 4

B) false