Abstract: An improved heating unit includes a water storage tank having an immersion heating element, with the water being pumped from the storage tank through the coils of a heat exchanger or condenser element. Ambient air is drawn over the coils and through a venturi transfer means to a hot air blower which then delivers the heated air to desired locations. The venturi duct between the heat exchanger and the blower insures a steady and efficient air flow over the condenser coils.