Heating is the process of raising the temperature in an enclosed space to ensure occupant comfort. The goal is to regulate ambient air temperatures, which can also help maintain the building’s structural, mechanical and electrical systems. The best HVAC companies—such as Rheem and Ruud—have extensive selections of heating units that are backed by solid warranties and high energy-efficiency ratings.

There are several types of residential heating units, including furnaces that supply heated air through ductwork, boilers that heat water for steam radiators or forced-water systems with baseboard heaters, and electric wall and portable heaters. Many of these systems use natural gas, propane, oil or electricity as a fuel source.

The capacity of your home and your heating and cooling needs should dictate the type of system you choose. Look for a unit that has the BTU rating (British Thermal Unit) and other specifications that reflect how much heat the appliance generates at its peak performance. You should also take into account your geographic location.

For example, in areas where winter temperatures are relatively mild, an air-source heat pump is a popular choice. These systems absorb heat from the air and distribute it through a series of ducts, but they’re not effective in very cold climates. For that reason, some homeowners choose to install a conventional gas or oil furnace as a backup heating system. You may also want to check out ductless mini-split heat pumps for a duct-free alternative. heating units