An exemplary embodiment of the present disclosure provides a flue gas outlet assembly including a flue gas inlet configured to connect to an exhaust outlet of a fuel burning device, a flue gas outlet, and a flue pipe condensate drain assembly including a condensate inlet, a condensate outlet, and a float valve disposed between the condensate inlet and the condensate outlet, the float valve including a bullet-shaped float, wherein the float valve is biased closed and is configured to open to permit a flow of condensate from the condensate inlet to the condensate outlet upon a sufficient amount of condensate collecting proximate the float valve.

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 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 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.

An exhaust pipe system for conducting exhaust gas from a combustion device to an exhaust system includes a first exhaust pipe with an inlet end and an outlet end, and a second exhaust pipe having a first line end and a second line end, wherein the inlet end of the first exhaust pipe is connectable to the first line end of the second exhaust pipe via a detachable coupling connection. A locking member is arranged to be movable between a closed position closing a passage and an open position opening the passage inside the first exhaust pipe. When the coupling connection is released, the locking member is automatically arranged in the closed position, and the second exhaust pipe has an actuating member which, when the coupling connection is established, urges the locking member into the open position.

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 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.