A ___ is used to prevent a dangerous vacuum from forming in a boiler when it is taken out of service.

Common types of hot water system valves include diverter fittings, three-way valves, and centrifugal valves.

A strainer should be installed before an RPZ backflow preventer to remove any foreign matter that could cause the preventer to malfunction.

A typical steam heating system operates at temperatures above ___°F.

___ heat is the ratio of the heat capacity of a substance to the heat capacity of a standard substance at the same temperature.

Gate valves are commonly used as feedwater stop valves.

A combination heating system uses all the components of a hot water heating system and a steam heating system.

Radiation has a major impact on all cooling systems.

Larger boilers are designed to use mechanical draft, which can be controlled more precisely and results in higher combustion efficiency.

Improper feedwater treatment is probably the largest direct cause of boiler failure.