BOC Boiler Systems and Steam

Question 1

What is the primary purpose of a boiler low-water cutoff?

Accepted Answer

To shut down the burner if water level drops too low

Answer

To regulate steam pressure

Answer

To control feedwater temperature

Answer

To prevent steam from entering the water supply

Question 2

Which type of boiler operates at steam pressures above 15 psig?

Accepted Answer

High-pressure boiler

Answer

Low-pressure boiler

Answer

Hot water boiler

Answer

Condensate boiler

Question 3

What does the term 'blowdown' refer to in boiler operation?

Accepted Answer

Removing accumulated solids and impurities from boiler water

Answer

Releasing excess steam pressure through a safety valve

Answer

Purging combustion gases from the firebox

Answer

Draining condensate from steam traps

Question 4

What is the function of a steam trap?

Accepted Answer

To discharge condensate and non-condensable gases while retaining steam

Answer

To increase steam pressure in distribution lines

Answer

To prevent steam from entering the condensate return line

Answer

To separate steam from feedwater

Question 5

A boiler's Hartford Loop is designed to protect against:

Accepted Answer

Siphoning of water out of the boiler

Answer

Overpressure conditions

Answer

Excessive flue gas temperatures

Answer

Waterlogging of steam radiators

Question 6

What does a boiler's 'stack temperature' indicate about combustion efficiency?

Accepted Answer

Lower stack temperatures generally indicate more heat is being extracted from the combustion gases

Answer

Higher stack temperatures always indicate better combustion

Answer

Stack temperature has no relationship to combustion efficiency

Answer

Optimal stack temperature is above 600°F for all boiler types

Question 7

Which chemical is commonly added to boiler feedwater to prevent oxygen corrosion?

Accepted Answer

Sodium sulfite or hydrazine

Answer

Sodium chloride

Answer

Calcium carbonate

Answer

Muriatic acid