A method for modulating a valve regulating the flow rate of gas towards a burner is presented. The valve with the associated closure member configured to operate with a predetermined characteristic curve, the flow rate delivered being proportionally related to the strength of a first current signal sent to the modulator such that the flow rate can be modulated, using the proportionality, within a range of modulation between a maximum flow rate and a minimum flow rate. To deliver controlled gas flow rates that are below the minimum flow rate, the modulator is driven with a second PWM voltage signal capable of generating a particular second PWM current signal, to move the closure member of the valve according to the second signal. First and second time intervals correspond to successive durations of high signal and low signal, respectively, the sum being equal to a period of the second signal.

A water heater may include a water tank, a burner, a pilot for igniting the burner, an ignitor for igniting the pilot, a thermoelectric device in thermal communication with a flame of the pilot, a controller for controlling an ignition sequence of the pilot using the ignitor, and a rechargeable power storage device for supplying power to the ignitor and the controller. The rechargeable power storage device may be rechargeable using the energy produced by the thermoelectric device. The controller is configured to selectively run only the pilot for at least part of a heating cycle to increase the recharge time of the rechargeable power storage device while still heating the water in the water heater.

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.

To heat a furnace chamber (16) indirectly using radiant tubes (11) to (14), heating energy is transferred through the radiant tube wall into the furnace chamber (16). During steady-state operation, the temperature in the radiant tube (11) to (14) and on its surface is higher than the furnace, depending on the specific heat output of the radiant tube (11) to (14). At a furnace temperature of 770 C. and a heat output of 50 kW/m2, the radiant tube has a temperature of 900 C. The radiant tube (11) to (14) can thus operate continuously with flameless oxidation at this output, even though the temperature in the furnace is only 100 C. However, if the radiant tube (11) to (14) has cooled to the furnace temperature of 770 C. during a break in burning, deflagration is avoided when the associated burner is ignited by initially operating said burner with a flame for a few seconds.

A gas manifold for a convection conveyor oven includes an elongated housing having a wall that at least partially encloses an interior volume; a gas inlet in fluid communication with the interior volume and extending through the wall; a plurality of gas outlets in fluid communication with the interior volume and extending through the wall; a plurality of seat inserts removably coupled with a plurality of gas outlets; a plurality of valve openings formed in the wall and aligned opposite the plurality of gas outlets; and at least one valve removably coupled to the wall and aligned with a first valve opening, wherein the valve is aligned with a first gas outlet and has a first position in which a first seat insert is not in fluid communication with the gas inlet.

A controller for a gas furnace, a computer-usable medium for implementing a method and a gas furnace are disclosed herein. In one embodiment, the controller includes: (1) an interface configured to receive a heating call and (2) a processor configured to enable an inducer of the gas furnace at a low speed based on the heating call and ignite the gas furnace at a high fire operation when determining a low fire pressure switch of the gas furnace is open.

Method for operating a gas burner appliance (10), the gas burner appliance com-prising: a combustion chamber (11) in which a defined gas/air mixture is combusted after combustion has been started; a mixing device (25) to provide said gas/air mixture by mixing an air flow provided by an air duct (15) with a gas flow provided by a gas duct (16); a fan (14) to provide the air flow or the flow of the gas/air mixture; a gas safety valve unit (19) assigned to the gas duct to open or close the gas duct; a gas flow modulator (18) or a gas flow regulator (28) assigned to the gas duct to keep a mixing ratio of the defined gas/air mixture constant over the modulation range of the gas burner appliance; an absolute pressure sensor (21) positioned between the gas safety valve unit and the mixing device, wherein the gas burner appliance is operated to determine the air flow resistance of the same by executing the following steps before combustion becomes started: Measuring a first absolute pressure by the absolute pressure sensor (21) when the gas safety valve unit (19) is closed and when the fan (14) is stopped. Measuring a second absolute pressure by the absolute pressure sensor (21) when the gas safety valve unit (19) is closed and when the fan (14) is running. Determining a pressure difference between the first absolute pressure and the second absolute pressure. Determining on basis of the pressure difference the air flow resistance of the gas burner appliance.

A burner includes an atomizing chamber, a flame tube in front of the atomizing chamber adapted to direct combusting fuel introduced by the atomizing chamber along an interior of the flame tube, and a controller. The controller is programmed to independently control rate of fuel flow to the atomizing chamber, rate of atomizing air flow to the atomizing chamber, and rate of combustion air to the flame tub. The controller is also programmed to perform operations including regulating, based on output of a gas sensor, at least the rate of combustion air to the flame tube to substantially maintain a first predetermined amount of excess air in the flame tube.

A modulating burner apparatus includes a variable speed blower feeding a multi-chamber burner having first and second burner chambers. A manifold system communicates the blower with the burner, and a flow control valve member is located between the blower and the second chamber of the burner. The flow control valve is configured to provide fuel and air mixture from the blower to only the first burner chamber at lower blower speeds of the blower and to both the first and second burner chambers at higher blower speeds of the blower.

A temperature control system for controlling the rate of flow of a flammable fluid at generally constant pressure is disclosed. The system may include a flow control apparatus that is free of a regulator mechanism, for affecting the flow of the fluid. The flow control apparatus may be operable between at least a first flow rate and a second flow rate, and may have at least one upstream opening and at least one downstream opening. The system may also include a first burner in fluid communication with the downstream opening of the flow control apparatus and a conduit in fluid communication at one end thereof with the upstream opening of the flow control apparatus, and configured at the other end thereof for connection to a fuel supply. A thermocouple may be located in the vicinity of the burner, for converting a sensed thermal state into an electrical signal. An electronic controller, in communication with the flow control apparatus, for activating the flow control apparatus to one of said first and second flow rates, and being in communication with the thermocouple for receiving the electrical signal from the thermocouple is also provided. An interface connected to the controller for manually inputting a desired temperature may be included, wherein the controller is operable to automatically cycle the flow control apparatus between the first and second flow rates until the temperature sensed by the thermocouple is similar to the desired temperature.