At sea level, a vacuum in a boiler results in a force of ___ lb applied on every square inch of surface.

A brick refractory should be cooled rapidly for energy efficiency.

When a circulating pump is not operating, the flow control valve closes to prevent natural circulation.

When an increase in steam pressure is required, the ___ activates the programmer to start a purge cycle and lights the pilot light.

A boiler room contains many combustible materials, and boiler room fire safety requires established procedures to reduce or eliminate conditions that could cause a fire.

When an increase in steam pressure is required, the ___ activates the programmer to start a purge cycle and lights the pilot light.

Fuel oil atomization temperature varies with the fuel oil grade and burner.

Well-designed burners firing gaseous and liquid fuels operate at excess air levels of about ___% and result in negligible amounts of unburned fuel.

A(n) ___ is an air pressure-activated switch that closes after proving sufficient pressure of combustion air from the forced draft fan.

A(n) ___ is an air pressure-activated switch that closes after proving sufficient pressure of combustion air from the forced draft fan.