In some examples, a gas/air mixing device configured to mix gas and air to provide a gas/air mixture includes a mixer housing with a mounting flange being configured to mount the gas/air mixing device to a fan housing in such a way that a sealing surface of the mounting flange is in contact with a sealing surface of the fan housing. In some examples, the sealing surface of the mounting flange has grooves with a second radius being different from the first radius. In some examples, the sealing surface of the fan housing has a groove, with a second radius being different from the first radius. The mixer housing provides an inlet opening for air, an inlet opening for gas, and an outlet opening for the gas/air mixture. The sealing surface of the mounting flange surrounds the outlet opening of the mixer housing.

In some examples, a gas/air mixing device configured to mix gas and air to provide a gas/air mixture includes a mixer housing with a mounting flange being configured to mount the gas/air mixing device to a fan housing in such a way that a sealing surface of the mounting flange is in contact with a sealing surface of the fan housing. In some examples, the sealing surface of the mounting flange has grooves with a second radius being different from the first radius. In some examples, the sealing surface of the fan housing has a groove, with a second radius being different from the first radius. The mixer housing provides an inlet opening for air, an inlet opening for gas, and an outlet opening for the gas/air mixture. The sealing surface of the mounting flange surrounds the outlet opening of the mixer housing.

Exemplary embodiments of a system and method for bimodal air control in a kettle-style grill are configured to be detachably mounted to the exterior of a kettle-styled grill such as, but not limited to, a Weber® charcoal grill. When mounted to the kettle-styled grill, a plenum-like component directs air flows to the interior of the grill's kettle via the kettle's lower body damper holes. A manually adjustable intake damper in the plenum component allows, restricts, or prevents a drawn ambient air flow into the plenum component. Separately, a forced air flow generated by a fan may also be provided into the plenum component. Adjustment of the intake damper may also adjust damper blades inside the grill's kettle. Ash that falls out of the kettle's damper holes falls through the plenum component and is captured in an ash receptacle that is removably mounted to the plenum component.

A flow control device for an appliance including a burner and a blower for delivering a pre-mixed mixture of air and gas to the burner includes a flange defining an opening through which the pre-mixed mixture of air and gas flows from an outlet of the blower to the burner. A damper plate is provided in the opening downstream of the blower for increasing a static pressure at the outlet of the blower during ignition of the burner.

A water heating device equipped with a housing, a fan and a chamber arranged in the interior of the housing, and screws. The housing has first and second side plates which oppose one another in a first direction and extend from the ends of a back plate along a second direction intersecting the first direction. An opening part is provided in the housing on the side opposite the back plate in the second direction. The fan has a discharge opening, a first flow passage extending along the first direction, and a first flange. The chamber has an intake opening, a second flow passage extending along the first direction, and a second flange. The first and the second flanges are secured by screws. In a planar view, the center axis of the screws is slanted such that a head portion is closer to the opening part than the tip-end portion.

A water heating device equipped with a housing, a fan and a chamber arranged in the interior of the housing, and screws. The housing has first and second side plates which oppose one another in a first direction and extend from the ends of a back plate along a second direction intersecting the first direction. An opening part is provided in the housing on the side opposite the back plate in the second direction. The fan has a discharge opening, a first flow passage extending along the first direction, and a first flange. The chamber has an intake opening, a second flow passage extending along the first direction, and a second flange. The first and the second flanges are secured by screws. In a planar view, the center axis of the screws is slanted such that a head portion is closer to the opening part than the tip-end portion.

A gas burner system has a gas burner with a conduit through which an air-gas mixture is conducted; a variable-speed forced-air device that forces air through the conduit; a control valve that controls a supply of gas for mixture with the air to thereby form the air-gas mixture; and an electrode configured to ignite the air-gas mixture so as to produce a flame. The electrode is further configured to measure a flame ionization current associated with the flame. A controller is configured to actively control the variable-speed forced-air device based on the flame ionization current measured by the electrode so as to automatically avoid a flame harmonic mode of the gas burner. Corresponding methods are provided.

A gas burner system has a gas burner with a conduit through which an air-gas mixture is conducted; a variable-speed forced-air device that forces air through the conduit; a control valve that controls a supply of gas for mixture with the air to thereby form the air-gas mixture; and an electrode configured to ignite the air-gas mixture so as to produce a flame. The electrode is further configured to measure a flame ionization current associated with the flame. A controller is configured to actively control the variable-speed forced-air device based on the flame ionization current measured by the electrode so as to automatically avoid a flame harmonic mode of the gas burner. Corresponding methods are provided.

Exemplary embodiments of a system and method for bimodal air control in a kettle-style grill are configured to be detachably mounted to the exterior of a kettle-styled grill such as, but not limited to, a Weber® charcoal grill. When mounted to the kettle-styled grill, a plenum-like component directs air flows to the interior of the grill's kettle via the kettle's lower body damper holes. A manually adjustable intake damper in the plenum component allows, restricts, or prevents a drawn ambient air flow into the plenum component. Separately, a forced air flow generated by a fan may also be provided into the plenum component. Adjustment of the intake damper may also adjust damper blades inside the grill's kettle. Ash that falls out of the kettle's damper holes falls through the plenum component and is captured in an ash receptacle that is removably mounted to the plenum component.

A gas furnace according to an embodiment of the present disclosure includes: a mixer for mixing air and a fuel gas, which are introduced through an intake pipe and a manifold, respectively, to form a mixture; a mixing pipe through which the mixture, having passed through the mixer, flows; a burner assembly for producing a combustion gas by burning the mixture having passed through the mixing pipe; a heat exchanger through which the combustion gas flows; an exhaust pipe through which an exhaust gas, as the combustion gas having passed through the heat exchanger, is discharged outside of the gas furnace; and an inducer for inducing a flow of a fluid through the intake pipe, the mixer, the mixing pipe, the burner assembly, the heat exchanger, and the exhaust pipe. In this case, the mixer has a front end connected to the intake pipe, a rear end connected to the mixing pipe, and a side surface connected to the manifold.