A vent proving system is described for use with a gas fired appliance. The gas fired appliance includes a gas burner, a vent damper for selectively opening or closing an exhaust vent from the gas fired appliance and a relay control for operatively controlling the vent damper and the gas burner to open the damper if the gas burner is on. The vent proving system comprises a sensor for sensing a variable in the vent representing air flow direction in the vent. An electrical switch is connected in series between the relay control and the vent damper. A controller is operatively connected to the sensor, the electrical switch and to the relay control.

A reactor system for the production and/or treatment of particles in an oscillating process gas stream. The reactor system includes a reactor unit that has an upstream feed unit and a downstream discharge unit and a reactor that includes a multiple burner system that has a combustion chamber, an exhaust gas pipe that follows downstream from the combustion chamber, and a plurality of burners. A part of the burners of the multiple burner systems are suitable for production of the oscillating process gas stream. The burners of the multiple burner system are arranged in the combustion chamber of the reactor unit.

Disclosed is a gas furnace including a mixer configured to mix air and fuel gas introduced from an intake pipe and a manifold respectively so as to produce an air-fuel mixture, a mixing pipe configured to allow the air-fuel mixture having passed through the mixer to flow therein, a burner assembly configured to combust the air-fuel mixture having passed through the mixing pipe so as to generate combustion gas, heat exchangers configured to allow the combustion gas to flow therein, an exhaust pipe configured to discharge exhaust gas, which is the combustion gas having passed through the heat exchangers, to the outside. The gas furnace further includes a recirculator installed around the exhaust pipe and configured to guide a portion of the exhaust gas flowing in the exhaust pipe to the mixer, and may thus greatly reduce or fundamentally block NO.sub.x emissions.

Disclosed is a gas furnace including a mixer configured to mix air and fuel gas introduced from an intake pipe and a manifold respectively so as to produce an air-fuel mixture, a mixing pipe configured to allow the air-fuel mixture having passed through the mixer to flow therein, a burner assembly configured to combust the air-fuel mixture having passed through the mixing pipe so as to generate combustion gas, heat exchangers configured to allow the combustion gas to flow therein, an exhaust pipe configured to discharge exhaust gas, which is the combustion gas having passed through the heat exchangers, to the outside. The gas furnace further includes a recirculator installed around the exhaust pipe and configured to guide a portion of the exhaust gas flowing in the exhaust pipe to the mixer, and may thus greatly reduce or fundamentally block NO.sub.x emissions.

A grill apparatus includes a bottom portion, a lid portion, a firebox and an ash bucket. The lid portion is coupled to the bottom portion forming a cooking chamber. The bottom portion receives the firebox. A support structure of the firebox rests on an inner surface of the bottom portion. An inner surface of the bottom port, the support structure of the firebox and a firebox lower opening define a first air path from a lower portion of the cooking chamber to a heat chamber. The ash bucket includes an air vent extending from a base of the ash bucket base into an internal ash receptacle and has an upper vent aperture with a vent cover connected to the air vent. The cover is disposed over an upper vent aperture to further define the first air path.

A grill apparatus includes a bottom portion, a lid portion, a firebox and an ash bucket. The lid portion is coupled to the bottom portion forming a cooking chamber. The bottom portion receives the firebox. A support structure of the firebox rests on an inner surface of the bottom portion. An inner surface of the bottom port, the support structure of the firebox and a firebox lower opening define a first air path from a lower portion of the cooking chamber to a heat chamber. The ash bucket includes an air vent extending from a base of the ash bucket base into an internal ash receptacle and has an upper vent aperture with a vent cover connected to the air vent. The cover is disposed over an upper vent aperture to further define the first air path.

A system to reduce standby losses in a hot water heater is presented. The system utilizes a dual safety relay valve between the combination gas controller and the burner. The dual safety relay valve bypasses gas to a rotary damper actuator valve to position a damper flapper valve located over/inside the flue pipe. Once the flapper valve has opened to ensure combustion, the gas is allowed to flow back to the dual safety relay valve. Some of the bypass gas may be diverted to boost the pilot or to supply a booster. The dual safety relay valve is then opened to allow the gas supply to the burner. Once the burner is turned off, bypass gas bleeds out of the rotary damper actuator valve to close the damper flapper valve to reduce standby losses through the flue pipe, and to allow the dual safety relay valve to close tightly.

Disclosed is a gas furnace including a mixer configured to mix air and fuel gas introduced from an intake pipe and a manifold respectively so as to produce an air-fuel mixture, a mixing pipe configured to allow the air-fuel mixture having passed through the mixer to flow therein, a burner assembly configured to combust the air-fuel mixture having passed through the mixing pipe so as to generate combustion gas, heat exchangers configured to allow the combustion gas to flow therein, an exhaust pipe configured to discharge exhaust gas, which is the combustion gas having passed through the heat exchangers, to the outside. The gas furnace further includes a recirculator installed around the exhaust pipe and configured to guide a portion of the exhaust gas flowing in the exhaust pipe to the mixer, and may thus greatly reduce or fundamentally block NOx emissions.

Disclosed is a gas furnace including a mixer configured to mix air and fuel gas introduced from an intake pipe and a manifold respectively so as to produce an air-fuel mixture, a mixing pipe configured to allow the air-fuel mixture having passed through the mixer to flow therein, a burner assembly configured to combust the air-fuel mixture having passed through the mixing pipe so as to generate combustion gas, heat exchangers configured to allow the combustion gas to flow therein, an exhaust pipe configured to discharge exhaust gas, which is the combustion gas having passed through the heat exchangers, to the outside. The gas furnace further includes a recirculator installed around the exhaust pipe and configured to guide a portion of the exhaust gas flowing in the exhaust pipe to the mixer, and may thus greatly reduce or fundamentally block NOx emissions.

A sealed chimney damper is provided for preventing flow of air between an interior and exterior of a structure through a chimney. The sealed damper includes a damper body having an inlet aperture and an outlet aperture; an upper flange formed around the outlet aperture of the damper body; a valve plate hingedly secured to the damper body adjacent the outlet aperture, the valve plate sized to substantially cover the outlet aperture when the valve plate is in a closed position; and a gasket secured to the upper flange of the damper body and surrounding the outlet aperture, wherein the gasket is positioned between the valve plate and damper body when the valve plate is in a closed position.