Boiler Systems and Steam Flashcards

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

Answer: To shut down the burner if water level drops too low

A low-water cutoff automatically shuts off the burner when water drops below a safe operating level to prevent overheating and damage to the boiler.

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

Answer: High-pressure boiler

High-pressure boilers are defined as those operating at steam pressures exceeding 15 psig, requiring more stringent safety and licensing requirements.

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

Answer: Removing accumulated solids and impurities from boiler water

Blowdown removes dissolved and suspended solids that concentrate in boiler water, preventing scale buildup and maintaining water quality.

What is the function of a steam trap?

Answer: To discharge condensate and non-condensable gases while retaining steam

Steam traps automatically discharge condensate and air from steam lines while blocking the passage of live steam, maintaining system efficiency.

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

Answer: Siphoning of water out of the boiler

The Hartford Loop prevents gravity-fed water from siphoning back out of the boiler through a return line leak, which could expose the heating elements.

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

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

Lower flue gas (stack) temperatures indicate that more heat is being transferred to the water, improving combustion efficiency and reducing energy waste.

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

Answer: Sodium sulfite or hydrazine

Oxygen scavengers such as sodium sulfite or hydrazine react with dissolved oxygen in feedwater, preventing pitting corrosion on boiler metal surfaces.