A system for electronically controlling a vent damper for a gas oven.

A controller monitors temperature in a bio-fuel fired device and automatically controls dampers, blowers and the like to reduce generation of smoke or other pollutants, thereby promoting proper operation of a catalytic converter.

A controller monitors oxygen levels in a bio-fuel fired device and automatically controls dampers, blowers and the like to reduce generation of smoke or other pollutants, thereby promoting proper operation of a catalytic converter.

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.

Techniques for controlling a solid fuel combustion appliance, e.g., a wood burning stove, are disclosed. A control system measures an exhaust gas temperature of airflow through an outlet of the solid fuel combustion appliance. The control system determines a derivative of the exhaust gas temperature with respect to time. The derivative of the exhaust gas temperature with respect to time is compared to a predetermined threshold. The control system modulates the inlet damper in response to determining that the derivative of the exhaust gas temperature with respect to time reaches the predetermined threshold.

Disclosed is a gas furnace for indoor heating. The gas furnace includes a burner to generate high-temperature exhaust gas, an exhaust flow path, a blower to suction indoor air through a recovery flow path, a supply flow path to guide the indoor air to the indoor space after undergoing heat exchange in the exhaust flow path, and a fuel supply unit including a fuel supply line and a fuel discharge line, configured to supply fuel to the burner, and a valve between the fuel supply line and the fuel discharge line. The valve includes a step motor, and a blocking member coupled to a rotating shaft of the step motor and configured to move straight via by driving of the step motor, and an opening degree of the valve between the fuel supply line and the fuel discharge line is adjusted by the straight movement of the blocking member.

A damper control device may include an appliance control programmed processor for controlling a gas burner, the appliance control programmed processor including a lockout register for storing electronic data information, and a damper control programmed processor for controlling a damper, the damper control programmed processor including a damper request register for storing electronic data information. The damper control programmed processor may be configured for selectively opening or closing the damper responsive to status of the damper request register and controlling status of the lockout register to indicate status of the damper, and the appliance control programmed processor may be configured for controlling status of the damper request register responsive to a call for operation of the gas burner and operating the gas burner only if the lockout register is in an unlock status.

An integrated damper control system is used with a gas fired appliance including a gas burner, a flue and a damper for selectively opening the flue. The damper control system comprises an appliance control including a programmed processor for controlling the gas burner and a communication interface device. A damper control comprises a programmed processor for controlling the damper and a communication interface device for communication with the appliance control communication interface device. The damper control programmed processor is programmed to selectively open or close the damper responsive to status of a damper request register and to control status of a lockout register to indicate status of the damper. The appliance control programmed processor is programmed to control status of the damper request register responsive to a call for operation of the gas burner and to operate the gas burner only if the lockout register is set to unlock.

Techniques for controlling a solid fuel combustion appliance, e.g., a wood burning stove, are disclosed. A control system measures an exhaust gas temperature of airflow through an outlet of the solid fuel combustion appliance. The control system determines a derivative of the exhaust gas temperature with respect to time. The derivative of the exhaust gas temperature with respect to time is compared to a predetermined threshold. The control system modulates the inlet damper in response to determining that the derivative of the exhaust gas temperature with respect to time reaches the predetermined threshold.

A coal-fired power generation system may include a boiler outputting flue gas, a coal pulverizer associated with the boiler, and a heat exchanger. The heat exchanger may be configured to exchange heat from the flue gas to a primary air path and a secondary air path. The primary air path is coupled to the coal pulverizer, and the secondary air path is coupled to the boiler. The coal-fired power generation system may include a controllable air recirculation path coupled from an output of the primary air path to an input of the secondary air path.