What is an Economizer?

• A. Heat exchanger used to reduce energy consumption
• B. A humidity analyzer
• C. A type of valve
• D. A control loop

Answer: (A)

An economizer is a heat exchanger placed in a boiler or steam-plant exhaust path that recovers heat from the hot exhaust gases. It transfers that heat to the incoming feedwater, preheating it before it enters the boiler. This preheating reduces the fuel needed to reach operating steam conditions, increasing overall efficiency and saving energy. That’s why the correct description is a heat exchanger used to reduce energy consumption. It isn’t a humidity analyzer, which would measure moisture content; it isn’t a valve, which regulates flow; and it isn’t a control loop, which provides feedback-based control. The essential idea is energy recovery through heat exchange to boost boiler efficiency.