Minnesota Boiler License Practice Exam

What is meant by the term low pressure boiler?

1. Boilers operating at 15 psig steam or 30 psig hot water

2. Boilers operating at a steam or other vapor pressure of 15 psig or less or a water or other liquid boiler in which the pressure does not exceed 160 psig or a temperature of 250 degrees F

3. 15 psig or less steam boilers, 60 psig hot water boilers

4. Boilers operating at 15 psig steam or other vapor and less than 232 degrees F hot water heater

The correct answer is: Boilers operating at a steam or other vapor pressure of 15 psig or less or a water or other liquid boiler in which the pressure does not exceed 160 psig or a temperature of 250 degrees F

The term "low pressure boiler" refers specifically to boilers that operate under certain pressure and temperature limits which define their classification. The correct definition states that low pressure boilers are those that have a steam or other vapor pressure of 15 psig or less. Additionally, for water or other liquid boilers, the pressure must not exceed 160 psig, nor should the temperature exceed 250 degrees Fahrenheit. This classification is crucial for safety and regulatory compliance in boiler operation. Understanding these limits is important for anyone working in this field, as it impacts the safety protocols, maintenance requirements, and operational procedures that must be followed. Many jurisdictions use these definitions to establish guidelines for inspections, operator qualifications, and pressure vessel standards. The other options either misstate these pressure limits or do not incorporate both the specific pressure and temperature criteria needed to accurately define a low pressure boiler.