Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

A method for controlling a gas furnace that performs a heating operation by receiving a first heating signal; calculating a certain heating capacity smaller than a maximum heating capacity of the gas furnace, according to the first heating signal; and operating a heating of the gas furnace with the calculated certain heating capacity. The calculating of the certain heating capacity includes calculating the certain heating capacity according to a difference between an intake air temperature sucked into the gas furnace and a reference temperature.

Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

The present invention is a method of optimizing radiant and thermal efficiency of a gas fired radiant tube heater. A heat exchange blower receives intake air and delivers intake air through a heat exchanger as pre-heated air to a combustion air blower. The combustion air blower receives pre-heated intake air from the heat exchanger and then provides the pre-heated intake air to a burner for mixing with fuel. The fuel-intake air mixture is burned in the burner thereby producing combustion gasses which are fired into a radiant tube. The exhaust combustion gases pass through the balance of the radiant tube and through the heat exchanger where residual heat is transferred and extracted from the combustion gases to pre-heat the intake air. The turbulators are configured to increase the turbulence within the radiant tube and are placed within the initial 10′ to 30′ of the radiant tube after the burner to increase the tube temperature and the radiation emitted from this section of the radiant tube.

A power burner system for use with a heating appliance includes a burner tube, a gas valve for providing gas to the burner tube, and a variable speed combustion air blower for mixing air with the gas provided to the burner tube. The burner system further includes a control in communication with the gas valve and the combustion air blower. The control may also be in communication with various other devices of an appliance, such as a variable speed air-circulating fan, a variable speed exhaust fan, or various sensors associated with the heating appliance. The control modulates the gas valve and the combustion air blower to maintain substantially stoichiometric conditions of the gas and air provided to the burner tube and as a function of signals from at least one of the devices. In one embodiment, the burner system may be used in a conveyor oven.

Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

Example furnaces and methods related thereto are disclosed herein. In an embodiment, the furnace includes a burner box including at least one burner configured to combust a fuel/air mixture. In addition, the furnace includes a first blower including an inlet nozzle having an air inlet and fuel inlet. The inlet nozzle is configured such that operation of the first blower is to pull air and fuel into the inlet nozzle to produce the fuel/air mixture at a fuel/air ratio that is configured to produce flue products having less than 14 Nano-grams per Joule of nitrogen oxides when combusted. Operation of the first blower is configured to push the fuel/air mixture into the burner box. Further, the furnace includes a heat exchanger assembly fluidly coupled to the burner box through a vestibule, and a second blower configured to pull the flue products through the heat exchanger assembly.

Example furnaces and methods related thereto include a burner box including at least one burner configured to combust a fuel/air mixture. In addition, the furnace includes a first blower including an inlet nozzle having an air inlet and fuel inlet. The inlet nozzle is configured such that operation of the first blower is to pull air and fuel into the inlet nozzle to produce the fuel/air mixture at a fuel/air ratio that is configured to produce flue products having less than 14 Nano-grams per Joule of nitrogen oxides when combusted. Operation of the first blower is configured to push the fuel/air mixture into the burner box. Further, the furnace includes a heat exchanger assembly fluidly coupled to the burner box through a vestibule, and a second blower configured to pull the flue products through the heat exchanger assembly.

Example furnaces and methods related thereto include a burner box including at least one burner configured to combust a fuel/air mixture. In addition, the furnace includes a first blower including an inlet nozzle having an air inlet and fuel inlet. The inlet nozzle is configured such that operation of the first blower is to pull air and fuel into the inlet nozzle to produce the fuel/air mixture at a fuel/air ratio that is configured to produce flue products having less than 14 Nano-grams per Joule of nitrogen oxides when combusted. Operation of the first blower is configured to push the fuel/air mixture into the burner box. Further, the furnace includes a heat exchanger assembly fluidly coupled to the burner box through a vestibule, and a second blower configured to pull the flue products through the heat exchanger assembly.

A furnace includes a controller configured to instruct a blower of the furnace to increase an exhaust flowrate of the furnace, instruct a gas regulation device of the furnace to increase a fuel input rate of the furnace, or both in response to a determination that the fuel input rate is below a threshold fuel input rate for a threshold time period. In some embodiments, the controller is configured to instruct the blower to maintain an increased exhaust flowrate for a flame-stabilizing time period the gas regulation device to maintain an increased fuel input rate for the flame-stabilizing time period, or both.