A premixing flow path forming member of a premixing device includes a member whose attachment mode can be changed, and flow path resistance of a fuel gas flow path can be changed when the attachment mode of the member is changed.

The present subject matter relates to a smoke tube boiler including: a mix chamber, a heat exchanger, a firing rod assembly, a sealing means, and an air-cooled cooling means and a water-cooled cooling means.

The present subject matter relates to a smoke tube boiler including: a mix chamber, a heat exchanger, a firing rod assembly, a sealing means, and an air-cooled cooling means and a water-cooled cooling means.

An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

[Problems to be Solved] An exhaust duct (4) for assembly into a combustion apparatus has: a burner (1) to eject air-fuel mixture downward; and a combustion box (3) disposed on a lower side of the burner (1). The exhaust duct includes: a riser duct section (42) elongated in a vertical direction and having, at a lower portion thereof, an inlet port (41) connected to an exhaust port (35) for combustion gas which is opened in a lower portion of the combustion box (3); and a flat horizontal duct section (43) bent at an upper end of the riser duct section (42) so as to be elongated forward. By restraining the resonance of an upper wall part (431) and a lower wall part (432) of the horizontal duct section (43), noises due to resonance sounds are reduced.

[Solving Means] The natural frequencies in an upper wall part (431) and the lower wall part (432) of the horizontal duct section (43) are varied from each other. For example, the lower wall part (432) is fixed to a burner body (11) in order to vary the natural frequencies of the upper wall part (431) and of the lower wall part (432) from each other.

The embodiments of the present application disclose a gas premix burner and a gas water heater. The gas premix burner has a combustion direction, the gas premix burner can be matched and connected with a premix chamber that is disposed upstream the combustion direction of the gas premix burner, gas and air can be burned by the gas premix burner after mixed in the premix chamber; the gas premix burner comprising: a burner substrate, a main combustion hole provided on the burner substrate; an auxiliary combustion hole disposed downstream the main combustion hole along the combustion direction on the burner substrate; an auxiliary flame of the auxiliary combustion hole intersects a main flame of the main combustion hole. The present application provides the main combustion hole upstream the auxiliary combustion hole along the combustion direction, since the main flame is usually larger in scale than the auxiliary flame, by providing the main flame upstream the auxiliary flame, it will be easier for the auxiliary flame and the main flame to intersect each other, and then the effect of stabilizing the flame is realized by opposed flames formed by the auxiliary flame and the main flame.

The present disclosure discloses an ignition temperature control apparatus of a gas water heater, comprising: a heat exchanger made of stainless steel; a combustion device which supplies high-temperature flue gas to the heat exchanger; a water passage communicated with the heat exchanger; a first temperature detection device provided on the heat exchanger or on the water passage; a controller, wherein if a temperature detected by the first temperature detection device is lower than or equal to a first preset temperature or a rate of decline of a temperature detected by the first temperature detection device is higher than or equal to a first preset value the controller controls the combustion device to operate in such a state that a requirement for thermal bearing capacity of the heat exchanger made of stainless steel is satisfied. The heat exchanger of the ignition temperature control apparatus of the gas water heater of the present disclosure, which is made of stainless steel, has good thermal inertia and excellent thermal insulation properties, and thus the combustion device is started for heating when the ignition temperature control apparatus of the gas water heater is in a stop state, such that it is possible to ensure that the heat exchanger will not fail while an anti-freezing effect can be achieved.

A high turn-down burner adapted to receive a fuel flow for combustion. The burner includes a housing having a side wall with an interior surface forming an inner periphery, a bottom wall adjoining the side wall, a top wall adjoining the side wall and a plurality of apertures disposed on the side wall; a supply tube adapted through the top wall of the housing, the supply tube including a side wall having an outer surface forming an outer periphery, a top end, a bottom end, wherein the supply tube is adapted to receive the fuel flow at the top end of the supply tube; and a disk having an opening adapted to accommodate the supply tube, wherein the disk is configured to slide along a length of the supply tube within the space delineated by the inner periphery of the housing and the outer periphery of the supply tube.

A water heater includes a primary heat exchanger, a secondary heat exchanger disposed above the primary heat exchanger, a flow path member, and a flow restriction member. The secondary heat exchanger includes a case and heat transfer pipes arranged in the case. The case includes a wall having a gas inlet through which combustion exhaust gas discharged from the primary heat exchanger is introduced into the case. The flow path member connects the primary heat exchanger and the secondary heat exchanger and is disposed adjacent to the gas inlet and is configured to introduce the combustion exhaust gas discharged from the primary heat exchanger into the secondary heat exchanger through the gas inlet. The flow restriction member is disposed on the wall of the case to suppress upward flowing of the combustion exhaust gas that is introduced into the case through the gas inlet.