A ___ is a narrowed portion of a tube.

The types of mechanical draft are forced, induced, and a combination of forced and induced.

The two common types of two-pipe systems are series systems and primary-secondary systems.

If accessible, gas lines should be checked for leaks by ___.

Rotary cup burners atomize fuel oil using a spinning cup and high-velocity air.

Rotary cup burners atomize fuel oil using a spinning cup and high-velocity air.

A(n) ___ is a common type of heat exchanger used to heat the air in a building space.

Cold makeup water reduces overall boiler efficiency because energy is required to ___ the water.

Air flow in a natural draft system is controlled as necessary through the ___.

Low-water cutoffs must be checked at least weekly or when local ordinances require.