A closing member includes an annular portion and a flange portion. The annular portion is provided with a through hole and is in contact with an outer circumferential surface of an exhaust tube in at least a part of the through hole. The flange portion extends from an outer circumferential surface of the annular portion toward an outer side and is larger in outer diameter than an exhaust pipe. The flange portion contacts a tip end portion of the exhaust pipe on outside of a building so as to close a gap between the exhaust pipe and the exhaust tube. The flange portion is formed to protrude toward an outer side such that an entire circumference of the flange portion extends beyond an outer circumferential surface of the tip end portion of the exhaust pipe.

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 sound level reducing apparatus and method for reducing the outdoor sound level produced by a high efficiency gas furnace. The apparatus comprising a muffler having an internal length determined by an identified target pure tone frequency producing an undesirable sound level. The internal length may be optimized to reduce the sound level across a range of operational frequencies.

The embodiments of the present application disclose a combustion control system of a gas water heater or wall-hanging boiler, and a control method thereof. The system comprises: a flue gas channel consisted of a combustor, a heat exchanger and a stepless speed regulating fan and a smoke tube, which are connected sequentially; a control unit connected to a signal input end of the stepless speed regulating fan; a wind pressure sensor assembly that detects a pressure signal upstream of an impeller of the stepless speed regulating fan, a signal output end of the wind pressure sensor assembly being connected to the control unit; the control unit comprising a storage for storing a correspondence relationship between the pressure signal upstream of the stepless speed regulating fan and a thermal load of the combustor, and a controller that controls operation of the stepless speed regulating fan according to the correspondence relationship. The present application further regulates the rotational speed of the stepless speed regulating fan by detecting the pressure signal upstream of the impeller of the stepless speed regulating fan, thereby achieving a better wind-resistant performance of the present application.

The embodiments of the present application disclose a combustion control system of a gas water heater or wall-hanging boiler, and a control method thereof. The system comprises: a flue gas channel consisted of a combustor, a heat exchanger and a stepless speed regulating fan and a smoke tube, which are connected sequentially; a control unit connected to a signal input end of the stepless speed regulating fan; a wind pressure sensor assembly that detects a pressure signal upstream of an impeller of the stepless speed regulating fan, a signal output end of the wind pressure sensor assembly being connected to the control unit; the control unit comprising a storage for storing a correspondence relationship between the pressure signal upstream of the stepless speed regulating fan and a thermal load of the combustor, and a controller that controls operation of the stepless speed regulating fan according to the correspondence relationship. The present application further regulates the rotational speed of the stepless speed regulating fan by detecting the pressure signal upstream of the impeller of the stepless speed regulating fan, thereby achieving a better wind-resistant performance of the present application.

Safety devices prevent packaged catalytic converters from being expelled from stacks, or at least reduce the velocity with which such a package may be expelled, in case of an explosion in a bio-fueled appliance, such as a wood-burning stove.

Safety devices prevent packaged catalytic converters from being expelled from stacks, or at least reduce the velocity with which such a package may be expelled, in case of an explosion in a bio-fueled appliance, such as a wood-burning stove.

A flue gas combustion apparatus for processing uncombusted flue gas components utilizing a reactor body. The reactor body houses first and second spiral passageways for motivating flue gas and ambient air, respectively, in a counter-current pattern. Heated ambient air feeds the flue gas in the reactor.

An apparatus and a method for achieving progressive reduction of flue gas is disclosed. Accordingly, an aspect of the present invention is to provide an apparatus comprising of an orifice chamber having an inlet pipe for receiving the flue gas, a flow region defined downstream of an exit of the inlet pipe and having at least a first section and a second section, and an outlet pipe to disperse a pressure reduced flue gas. The first section defined downstream of the inlet pipe has a flow developer means and at least one auxiliary orifice plate. The second section defined downstream of the first section has a plurality of orifice plates spaced apart along a flow length of the second section.

An apparatus and a method for achieving progressive reduction of flue gas is disclosed. Accordingly, an aspect of the present invention is to provide an apparatus comprising of an orifice chamber having an inlet pipe for receiving the flue gas, a flow region defined downstream of an exit of the inlet pipe and having at least a first section and a second section, and an outlet pipe to disperse a pressure reduced flue gas. The first section defined downstream of the inlet pipe has a flow developer means and at least one auxiliary orifice plate. The second section defined downstream of the first section has a plurality of orifice plates spaced apart along a flow length of the second section.