Kansas Mechanical Journeyman Practice Exam - Prep, Questions & Study Guide

The purpose of an air handler in an HVAC system is to circulate conditioned air throughout a building. Air handlers are key components that take in air, condition it—by heating or cooling—and then redistribute it through the ductwork to maintain a consistent and comfortable environment within a space. This circulation is essential for ensuring that the temperature and air quality remain stable across various rooms and areas of the building.

While air handlers can also have filtration capabilities, their primary function focuses on air circulation. The filtration processes in an air handler help clean the air, but it's important to note that the main role involves moving the air. Humidity control can be a function of the overall HVAC system but isn't the primary job of the air handler itself. Heating water for domestic use is unrelated to the role of an air handler, as that function typically falls under a water heater or boiler.