Chapter 3 Flashcards
Quiz 3
How is the number of blowdowns determined by water chemistry?
The more the impurities, the more blowdowns must be performed
The number of blowdowns required is determined by _______
Water Chemistry
A boiler with very clean water does not require water treatment.
False
A boiler with water at a pH level of 7 will be considered alkaline/basic.
False
Oxygen causes:
corrosion and pitting
If substance has a pH level that is above 7 is considered to be:
Basic
If substance has a pH level that is 7 it is considered to be:
Neutral
If substance has a pH level that is below 7 it is considered to be:
neither neutral nor basic
When a boiler has an unsafe level of water, what device is electronically activated ?
Fuel solenoid valve- which shuts off the fuel supply
As solids and alkalinity in boiler water increase
waterside scaling is increased
Which of the following would cause scale to form in a low pressure boiler?
Calcium and magnesium
Blowing down is most effective when the steam output is ________
at a low rate
A pressure reducing valve (PRV) is used on a feedwater line when the domestic water supply is city water.
True
Impurities that increase the density of the boiler water are removed by:
both bottom and surface blowdown
What chemical would be used to control alkalinity in a boiler?
Caustic soda
Why should the gauge glass on a steam boiler be blown down regularly?
to remove dirt and sediment from the glass
Bottom blowdown works best when the boiler is in high fire
False
The primary function of adding make-up water to a system is to:
to replace water lost through evaporation, leaks, or other processes
What will excessive oxygen in the boiler water cause to take place?
pitting of boiler metal
Sediment can be removed by performing a bottom blowdown.
True
What chemical would be used to control scale in a low pressure boiler?
Phosphate
Boiler water is treated to remove nitrogen from the water.
False
The main reason make-up water is added to the boiler is to:
Replenish water that has been lost and to supply enough water to keep the proper amount of steam flowing
