The present invention relates to a method of controlling a gas furnace that performs heating operation according to a heating signal formed of one of a weak heating signal and a strong heating signal. The method includes: (a) receiving the heating signal; (b) determining whether the heating signal is the weak heating signal or the strong heating signal; (c) calculating a certain weak heating capacity smaller than a maximum heating capacity of the gas furnace, when the heating signal is the weak heating signal; and (d) operating a weak heating of the gas furnace with the calculated certain weak heating capacity, wherein the step (c) includes calculating the weak heating capacity according to a difference between a temperature of air (hereinafter, an intake air temperature) sucked into the gas furnace and a reference temperature set based on the intake air temperature.

A high-efficiency modulating gas furnace (herein gas furnace) includes a furnace controller. The gas furnace further includes a gas valve and at least one pressure switch that is coupled to the furnace controller. The electrical contacts of the at least one pressure switch are removed from a series electrical circuit with the gas valve such that the gas furnace operates without de-energizing the gas valve as soon as the electrical contacts of the at least one pressure switch are opened. Further, the furnace controller operates the induced draft blower at or close to a lowest RPM at which the electrical contacts of the at least one pressure switch can be kept closed, which is between a make point RPM at which the electrical contacts of the at least one pressure switch close and a break point RPM at which the electrical contacts of the at least one pressure switch open.

The present invention relates to a method of controlling an RPM of a blower for a gas furnace that passes air to be supplied to a room around a heat exchanger of a gas furnace. The method includes: starting operation of the gas furnace; measuring an air temperature in an outlet side of the gas furnace; measuring the RPM of the blower; determining whether the air temperature falls within a reference temperature range; and adjusting the RPM of the blower such that the air temperature falls within the reference temperature range.

A method of controlling an RPM of a blower for a gas furnace that passes air to be supplied to a room around a heat exchanger of a gas furnace, the method including starting operation of the gas furnace; measuring an air temperature in an outlet side of the gas furnace; measuring the RPM of the blower; determining whether the air temperature falls within a reference temperature range; and adjusting the RPM of the blower such that the air temperature falls within the reference temperature range.

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 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.

A control module for preventing acoustic resonance noise generation from a heat exchanger of a heating furnace, comprising a control signal generated by the control module. The control signal is configured to operate an induction fan of the heating furnace at more than one speed for a given heat demand mode of the heating furnace.

A high-efficiency modulating gas furnace (herein gas furnace) includes a furnace controller. The gas furnace further includes a gas valve and at least one pressure switch that is coupled to the furnace controller. The electrical contacts of the at least one pressure switch are removed from a series electrical circuit with the gas valve such that the gas furnace operates without de-energizing the gas valve as soon as the electrical contacts of the at least one pressure switch are opened. Further, the furnace controller operates the induced draft blower at or close to a lowest RPM at which the electrical contacts of the at least one pressure switch can be kept closed, which is between a make point RPM at which the electrical contacts of the at least one pressure switch close and a break point RPM at which the electrical contacts of the at least one pressure switch open.

A control module for preventing acoustic resonance noise generation from a heat exchanger of a heating furnace, comprising a control signal generated by the control module. The control signal is configured to operate an induction fan of the heating furnace at more than one speed for a given heat demand mode of the heating furnace.

The invention relates to a heating device, in particular for mobile use, comprising a combustion chamber for reacting fuel with combustion air in order to release heat, a heat exchanger for transferring at least part of the released heat to a heating medium to be heated, a fuel conveying device for supplying fuel to the combustion chamber, a combustion air fan for supplying combustion air to the combustion chamber, a heating medium fan for supplying the heating medium to the heat exchanger, a common drive for the combustion air fan and the heating medium fan, at least one sensor for monitoring the mass flow of the heating medium, and a controller, which controls the fuel conveying device and the common drive. The controller is designed to change the ratio of the amount of the heating medium and the amount of the fuel supplied to the combustion chamber according to the mass flow of the heating medium.