In a direct-expansion system, the condenser can be a shell-and-coil, a shell-and-tube, or a tube-in-tube heat exchanger.

The amount of energy required to raise the temperature of 1 lb of water 1°F is 1 ___.

A ___ boiler is a boiler in which heat and gases of combustion pass through tubes surrounded by water.

A ___ boiler is a boiler in which heat and gases of combustion pass through tubes surrounded by water.

The purpose of the water column of a boiler is to reduce water turbulence, allowing the true boiler water level to be indicated by the water level in the gauge glass.

The purpose of the water column of a boiler is to reduce water turbulence, allowing the true boiler water level to be indicated by the water level in the gauge glass.

The ___ is charged with establishing and enforcing the Clean Air Act.

A safety inspector is a person who is trained in, and has specific knowledge of, the construction and operation of electrical equipment or a specific task, and is trained to recognize and avoid electrical hazards that might be present with respect to the equipment or specific task.

The water level in a gauge glass should be out of sight during bottom blowdown.

Perfect combustion is combustion that occurs when all the fuel is burned with a minimum amount of excess air remaining.