The disclosed technology includes a device for extending the turndown ratio of a gas-fired burner system. The device can comprise a variable area device configured reduce the amount of fuel and air passed to the burner during low output conditions by adjusting the cross-sectional area of the passage between the blower and the burner. The variable area device can be controlled by an actuator that adjusts the position of the variable area device. The actuator can be manually controlled, mechanically controlled, or electronically controlled.

The disclosed technology includes a device for extending the turndown ratio of a gas-fired burner system. The device can comprise a variable area device configured reduce the amount of fuel and air passed to the burner during low output conditions by adjusting the cross-sectional area of the passage between the blower and the burner. The variable area device can be controlled by an actuator that adjusts the position of the variable area device. The actuator can be manually controlled, mechanically controlled, or electronically controlled.

A modulating burner apparatus includes a burner and a blower placed upstream of the burner. A venturi is placed upstream of the blower. A damper valve is placed upstream of the venturi. The damper valve has an open position and a restricted position. A smaller gas valve and a larger gas valve are communicated with the venturi. A controller is operably associated with the system to select a position of the damper valve and to select the appropriate one of the gas valves so as to provide a low output operation mode and a high output operation mode, which in combination provide an overall turndown ratio of at least 25:1.

A modulating burner apparatus includes a burner and a blower placed upstream of the burner. A venturi is placed upstream of the blower. A damper valve is placed upstream of the venturi. The damper valve has an open position and a restricted position. A smaller gas valve and a larger gas valve are communicated with the venturi. A controller is operably associated with the system to select a position of the damper valve and to select the appropriate one of the gas valves so as to provide a low output operation mode and a high output operation mode, which in combination provide an overall turndown ratio of at least 25:1.

The present invention provides a hot water storage-type boiler having both a heat amount proportional control function and a backflow prevention function to prevent a backflow of exhaust gas with a simple structure. In the present invention, since a check valve is integrally coupled to a burner duct, there is an effect of convenient assembly. In addition, since the check valve is built in the burner duct, the check valve does not protrude to the outside, thereby having an effect that a separate space is not required.

The present invention provides a hot water storage-type boiler having both a heat amount proportional control function and a backflow prevention function to prevent a backflow of exhaust gas with a simple structure. In the present invention, since a check valve is integrally coupled to a burner duct, there is an effect of convenient assembly. In addition, since the check valve is built in the burner duct, the check valve does not protrude to the outside, thereby having an effect that a separate space is not required.

The disclosed technology includes a device for extending the turndown ratio of a gas-fired burner system. The device can comprise a variable area device configured reduce the amount of fuel and air passed to the burner during low output conditions by adjusting the cross-sectional area of the passage between the blower and the burner. The variable area device can be controlled by an actuator that adjusts the position of the variable area device. The actuator can be manually controlled, mechanically controlled, or electronically controlled.

The disclosed technology includes a device for extending the turndown ratio of a gas-fired burner system. The device can comprise a variable area device configured reduce the amount of fuel and air passed to the burner during low output conditions by adjusting the cross-sectional area of the passage between the blower and the burner. The variable area device can be controlled by an actuator that adjusts the position of the variable area device. The actuator can be manually controlled, mechanically controlled, or electronically controlled.

A firebox for an outdoor cooking system has a gas burner positioned inside the firebox housing. The gas burner has a built-in altitude adjustment mechanism that allows for adjustment of proper air/gas mixture for cooking at different altitudes. An air deflector configured as an enclosing wall encloses the gas burner so as to greatly reduce the flow of unwanted air/wind disruptions to the flame/heat output of the gas burner.

A firebox for an outdoor cooking system has a gas burner positioned inside the firebox housing. The gas burner has a built-in altitude adjustment mechanism that allows for adjustment of proper air/gas mixture for cooking at different altitudes. An air deflector configured as an enclosing wall encloses the gas burner so as to greatly reduce the flow of unwanted air/wind disruptions to the flame/heat output of the gas burner.