A heating coil is a heat exchanger that raises the temperature of air passing through an HVAC system by transferring thermal energy from a heat source such as hot water, steam, or electricity. These coils are essential components in forced-air heating systems, installed in ductwork or air handling units to condition incoming air for residential and commercial spaces.
Technical Details
Heating coils consist of metal tubing (typically copper or aluminum) arranged in rows with fins to maximize surface area. Operating temperatures range from 140°F to 180°F for hot water coils and up to 250°F for steam coils. The coil’s heating capacity is measured in BTU/h and depends on inlet water temperature, flow rate, and air velocity across the coil face.
Applications and Significance
Heating coils serve primary or supplemental heating functions in packaged units, make-up air handlers, and zone heating systems. They’re commonly used in commercial buildings, hospitals, and industrial facilities. Proper sizing ensures adequate heat output while maintaining system efficiency and preventing excessive pressure drop in the HVAC circuit.