Chapter 17 Heating Boiler Operating Controls

Question 1

The burner control that continually adjusts the firing rate to maintain the boiler pressure at a constant value is called ________.

a) On-off
b) High-low
c) Modulating
d) High limit

Answer 1

c) Modulating

Question 2

The name of the second spring that is used to increase the span between cut-in and cut-out is the _______ control.

a) Differential
b) High-low
c) Mid spring
d) Set point

Answer 2

a) Differential

Question 3

The simplest type of burner operating control used on low capacity boilers is the _________.

a) Modulating
b) High-low
c) High limit
d) On-off

Answer 3

d) On-off

Question 4

The device used on hot water boilers to maintain the water temperature is the _________.

a) Immersion bulb
b) Bellows
c) Modulator
d) Aquastat

Answer 4

d) Aquastat

Question 5

The name of the switch used to start or stop the boiler is the _______.

a) Selector
b) Burner
c) Flame Control
d) High-low

Answer 5

b) Burner

Question 6

If the low air pressure switch is activated it will close the _______.

a) Damper
b) Main fuel valve
c) Pilot gas valve
d) Feedwater valve

Answer 6

b) Main fuel valve

Question 7

The cut-out pressure setting for a high pressure safety control used to protect a low-pressure steam boiler will be:

a) 103 kPa
b) Lower than the cut-out pressure of the operating control
c) Just below the popping pressure
d) No higher than 200 kPa

Answer 7

c) Just below the popping pressure