What Does the Hydro Pump Do on an Air Handling Unit?

What Does the Hydro Pump Do on an Air Handling Unit?

The hydro pump on an air handling unit, or air handler, circulates hot water between the water heater and the hydronic heating coil. In an air handling unit, a tankless water heater serves as the heat source, providing the home with hot water and heat simultaneously.

Not all air handling units have a hydro pump. As detailed by Allen Bernard, a facility maintenance advisor for Welsh & Colliers International, an air handling unit conditions and circulates air within an HVAC system. The typical components are a blower, heating or cooling elements, filter racks, sound attenuators and dampers. Normally air handlers are connected to ductwork used to distribute conditioned air through a building or home and return it to the unit. Small air handlers, known as terminal units, are usually comprised of only an air filter, coil and blower.

A hydro pump is found on air handling units that are part of an integrated heating and water systems, such as the one manufactured by Rheem. A hydronic air handler features a heating coil rather than electric or gas-fired heating elements. When in heating mode, the hydro pump moves the hot water to and from the coil, thus being critical to the HVAC’s ability to provide heat to a building.