A nonreturn valve for an exhaust pipe of a combustion device comprising including a tubular body, a floating body, a valve seat for the floating body disposed inside the tubular body, and a circumferential groove disposed radially inside the tubular body, wherein a radial inner circumferential wall portion is formed at least as a portion of a gas guide channel extending in the direction of the floating body and having a mouth circumferential edge. A tubular buoyancy body having the valve seat is disposed inside the circumferential groove and is formed to be movable in parallel to the radial inner circumferential wall portion between a buoyancy position in which the buoyancy body forms between itself and the mouth circumferential edge a circumferential passage gap connecting the circumferential groove to the gas guide channel and a blocking position closing the passage gap in an axial direction.

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.

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 non-return valve having an accumulation damper movable relative to a housing and shaped like a bowl to accumulate condensate running down from the chimney. The non-return valve has a smaller floating damper made of a material having a density less than water for resting against the accumulation damper when the appliance is in standstill and sealing the drainage holes in the accumulation damper when the condensate accumulation is below a threshold. Once condensate accumulates in the accumulation damper beyond the threshold, the floating damper is buoyed by the condensate thereby breaking the seal with the drainage holes and permitting the condensate to drain through drainage holes in the accumulation damper. When the appliance is operational, exhaust from the appliance lifts the floating damper and, in some cases, the accumulation damper also, to permit exhaust of combustion gases up the chimney.

A non-return valve having an accumulation damper movable relative to a housing and shaped like a bowl to accumulate condensate running down from the chimney. The non-return valve has a smaller floating damper made of a material having a density less than water for resting against the accumulation damper when the appliance is in standstill and sealing the drainage holes in the accumulation damper when the condensate accumulation is below a threshold. Once condensate accumulates in the accumulation damper beyond the threshold, the floating damper is buoyed by the condensate thereby breaking the seal with the drainage holes and permitting the condensate to drain through drainage holes in the accumulation damper. When the appliance is operational, exhaust from the appliance lifts the floating damper and, in some cases, the accumulation damper also, to permit exhaust of combustion gases up the chimney.

A flue damper may include a vent pipe with a first side leading to an outlet of the flue damper and a second side leading to an inlet of the flue damper. The flue damper may further include a damper gate with an open state and a closed state, where in the open state, the first side of the vent pipe is in fluid communication with the second side, and where in the closed state, the damper gate interrupts fluid communication between the first side and the second side. A seat flange may be located on an inner wall of the vent pipe, and a seal may be fixed to an outer edge of the damper gate, where a through-portion of the seal extends through a first perforation in the outer edge of the damper gate.

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 home cooking appliance includes a housing having a cooktop surface on a top of the housing, a burner on the cooktop surface, a cooking grate disposed above the burner, a cooking compartment in the housing, an oven flue that exhausts air from the cooking compartment, and a flue gas air diverter configured to divert the air exiting from the oven flue under a portion of the cooking grate.

The present invention relates to a reverse flow prevention apparatus for common exhaust flue and a combustion apparatus having same. The reverse flow prevention apparatus for common exhaust flue, which is configured to collect exhaust gas of a plurality of combustion apparatuses, discharge the collected exhaust gas through a common exhaust flue, and prevent a reverse flow of the exhaust gas from the common exhaust pipe to each of the combustion apparatuses, includes a flange coupled to an exhaust port of each of the combustion apparatuses, an opening and closing apparatus hinge-coupled to an upper part of the flange to be opened and closed by a pressure difference between a lower portion and an upper portion thereof, and a body coupled to the upper part of the flange so as to accommodate the opening and closing apparatus. In accordance with the present invention, the reverse flow prevention apparatus, which may be directly installed at the exhaust port of the combustion apparatus, is coupled to the common exhaust flue upon installation thereof so that a separate certification may not be required to reduce time and costs for a certification.

The present invention relates to a reverse flow prevention apparatus for common exhaust flue and a combustion apparatus having same. The reverse flow prevention apparatus for common exhaust flue, which is configured to collect exhaust gas of a plurality of combustion apparatuses, discharge the collected exhaust gas through a common exhaust flue, and prevent a reverse flow of the exhaust gas from the common exhaust pipe to each of the combustion apparatuses, includes a flange coupled to an exhaust port of each of the combustion apparatuses, an opening and closing apparatus hinge-coupled to an upper part of the flange to be opened and closed by a pressure difference between a lower portion and an upper portion thereof, and a body coupled to the upper part of the flange so as to accommodate the opening and closing apparatus. In accordance with the present invention, the reverse flow prevention apparatus, which may be directly installed at the exhaust port of the combustion apparatus, is coupled to the common exhaust flue upon installation thereof so that a separate certification may not be required to reduce time and costs for a certification.