Abstract: In a temperature adjusting system, a first temperature measuring unit measures the temperature at a blowing outlet port supplying a temperature control space with a medium and a first temperature controller provides compensation responsive to the first measured temperature. A second temperature measuring unit measures the temperature of the temperature control space downstream of the blowing outlet port and a second temperature controller provides compensation responsive to second measured temperature. A temperature converting unit controls heat generation on the basis of the first temperature controller output to control the medium at the constant temperature supplied from the blowing outlet port. A set predetermined temperature corresponding to a desired value for the temperature in the temperature control space is input to the second temperature controller and the second temperature controller output is input as a temperature value to the first temperature controller.

Abstract: An apparatus for reducing the concentration of nitrogen oxides in flue gases produced in a furnace of a combustion unit includes a device for maintaining combustion reactions in the furnace, the combustion reactions resulting in the production of hot gases containing nitrogen oxides, the hot gases flowing mainly upwardly within the furnace, internal heat transfer surfaces within the furnace for recovering heat from the mainly upward flow of hot gases, an introducer for introducing nitrogen oxides reducing agent into the upward flow of hot gases in the furnace, for reducing the concentration of nitrogen oxides in the hot gases, wherein the introducer is integrally connected to the internal heat transfer surfaces, for keeping the temperature of the reducing agent at a sufficiently low temperature level upon introduction thereof into the furnace, and for efficiently mixing the reducing agent with the upward flow of hot gases, and a discharge for discharging flue gases from the furnace.

Abstract: A hot water tank construction, an electrically operated heating element construction therefor and methods of making the same are provided, the electrically operated heating element construction comprising a heating element and an externally threaded fitting for threading into an internally threaded opening in a wall of the tank, the heating element comprising an outer metallic tubular sheath and an inner conductive heater wire insulated from the sheath, the fitting comprising polymeric material, the heating element construction comprising an electrical resistance electrically interconnected to the sheath and being adapted to electrically interconnect the sheath to the wall of the tank, the polymeric material comprising an electrically conductive polymeric material that also comprises the resistance of the heating element construction.