Systems and Methods for Avoiding Harmonic Modes of Gas Burners

2:

• The gas burner system according to claim 1, wherein the gas burner is a fully premixed gas burner in which all air introduced into the conduit is introduced via the variable-speed forced-air device.

3:

• The gas burner system according to claim 1, wherein the control valve comprises a solenoid having a closed position preventing flow of gas there through and a wide open position allowing flow of gas there through.

4:

• The gas burner system according to claim 3, wherein the control valve comprises a pair of outlet ports that discharge the gas, and wherein the solenoid is one of a pair of solenoids that independently control discharge of the gas via the pair of outlet ports to the gas burner, and wherein the control valve facilitates four discrete power settings, including off wherein both solenoids are fully closed, low wherein one of the solenoids is fully closed and the other of the solenoids is fully open, medium wherein the one of the solenoids is fully open and the other of the solenoids is fully closed, and high wherein both of the solenoids are fully open.

5:

• The gas burner system according to claim 3, wherein the controller is configured to control the variable-speed forced-air device at a plurality of power settings, each having a minimum fan speed and each power setting providing a discrete setting for heat input by the gas burner system.

6:

• The gas burner system according to claim 1, wherein the controller is configured to automatically avoid the flame harmonic mode of the gas burner by controlling the variable-speed combustion blower so that the air-gas mixture maintains a Reynolds number of greater than 1000 and an air-fuel equivalence ratio of greater than 1.2.

7:

• The gas burner system according to claim 1, wherein the gas burner comprises a plurality of aeration holes through which the air-gas mixture is forced by the variable-speed forced-air device.

8:

• The gas burner system according to claim 7, wherein the gas burner comprises a flame tube through which the air-gas mixture is conveyed, a burner deck covering the flame tube, wherein the plurality of aeration holes is formed through the burner deck, and a burner skin covering the plurality of aeration holes.

9:

• The gas burner system according to claim 8, wherein the burner skin comprises a metal woven mat.

10:

• The gas burner system according to claim 8, wherein the plurality of holes consists of 33 aeration holes having a diameter of between 1.9 and 2.1 mm.

11:

• The gas burner system according to claim 10, wherein the plurality of holes consists of a first group of three holes that are spaced equidistant from each other and surrounded by a second group of eleven holes that are spaced equidistant from each other and surrounded by a third group of nineteen holes that are spaced equidistant from each other.

12:

• The gas burner system according to claim 11, wherein the second and third groups of holes form concentric circles around the first group of holes.

13:

• The gas burner system according to claim 8, further comprising a heat exchanger, wherein the gas burner is coupled to the heat exchanger so that heat generated by the gas burner heats the heat exchanger.

14:

• The gas burner system according to claim 13, further comprising a housing that contains the heat exchanger and gas burner, wherein the housing comprises an upstream cool air inlet that receives relatively cool air and a downstream warm air outlet that discharges relatively warm air, and a fan that forces air into the upstream air inlet, across the heat exchanger, and out of the downstream air outlet.

15:

• The gas burner system according to claim 14, further comprising a combustion intake port on the housing through which air for combustion in the gas burner is drawn by the variable-speed forced-air device and a combustion exhaust port on the housing through which air from the gas burner is forced by the variable-speed forced air device.

16:

• The gas burner system according to claim 14, further comprising an end cap on the variable-speed forced-air device, wherein the control valve is mounted on the end cap.

17:

• The gas burner system according to claim 1, further comprising an indicator device that indicates to an operator if the controller is unable to control the variable-speed forced-air device to achieve a minimum flame strength.

19:

• The method according to claim 18, wherein the gas burner is a fully premixed gas burner in which all air introduced into the gas burner is via the variable-speed forced-air device.

20:

• The method according to claim 18, further comprising controlling the variable-speed forced-air device at a plurality of power settings, each having a minimum fan speed, each power setting providing a discrete setting for heat input by the gas burner system.

21:

• The method according to claim 18, further comprising operating the controller to automatically avoid the flame harmonic mode of the gas burner by controlling the variable-speed combustion blower so that the air-gas mixture maintains a Reynolds number of greater than 1000 and an air-fuel equivalence ratio of greater than 1.2.

22:

• The method according to claim 18, further comprising indicating via an indicator device when the controller is unable to control the variable-speed forced-air device to achieve a target flame ionization current.

24:

• The gas burner system according to claim 23, wherein the second and third groups of holes form concentric circles around the first group of holes.

25:

• The gas burner system according to claim 23, wherein the burner skin comprises a metal woven mat.