Combustion acoustic noise prevention in a heating furnace

Patent metadata

Field	Value
Publication number	US-10344975-B2
Application number	US-201815957310-A
Country	US
Kind code	B2
Filing date	Apr 19, 2018
Priority date	Jul 24, 2012
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

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.

First claim

What is claimed is:

1. A heating furnace comprising:
a control module, wherein the control module is configured to generate a control signal, wherein the control signal is configured to:
for a given heat demand mode of the heating furnace, operate an induction fan of the heating furnace at more than one fan speed;
in response to a request for a high heat demand mode of the heating furnace, operate the induction fan at a low fan speed during flame ignition within a burner and for a stabilization period after the flame ignition within the burner; and
operate the induction fan at a high fan speed following the stabilization period; and
wherein the low fan speed is less than a higher fan speed designed to support the heating furnace operating at a maximum rated thermal output.

2. The heating furnace of claim 1 , wherein the control signal is configured to regulate a fuel supply rate to the burner.

3. The heating furnace of claim 2 , wherein, in a low heat demand mode, the fuel supply rate is lower than the fuel supply rate in a high heat demand mode.

4. The heating furnace of claim 1 , wherein the low fan speed is a value in a range from about 25 percent less to about 75 less than the higher fan speed.

5. The heating furnace of claim 1 , wherein the stabilization period is at least about 3 seconds.

6. The heating furnace of claim 1 , wherein the stabilization period is a value in a range from 5 to 60 seconds.

7. The heating furnace of claim 1 , wherein the heating furnace is a single-stage heating furnace having a single demand mode corresponding to a maximum rated thermal output of the heating furnace.

8. A control module comprising:
a circuit board configured to generate a control signal, wherein the control signal is configured to:
for a given heat demand mode of a heating furnace, operate an induction fan of the heating furnace at more than one fan speed;
in response to a request for a high heat demand mode of the heating furnace, operate the induction fan at a low fan speed during flame ignition within a burner and for a stabilization period after the flame ignition within the burner;
operate the induction fan at a high fan speed following the stabilization period;
wherein the low fan speed is less than a higher fan speed designed to support the heating furnace operating at a maximum rated thermal output.

9. The control module of claim 8 , wherein the low speed is a value in a range from about 25 percent less to about 75 less than the higher speed.

10. The control module of claim 8 , wherein the stabilization period is at least about 3 seconds.

11. The control module of claim 8 , wherein the stabilization period is a value in a range from 5 to 60 seconds.

12. The control module of claim 8 , wherein the control signal is configured to regulate a fuel supply rate to the burner.

13. The control module of claim 12 , wherein, in a low heat demand mode, the fuel supply rate is lower than the fuel supply rate in a high heat demand mode.

14. A method of preventing acoustic resonance noise generation from a heat exchanger of a heating furnace, the method comprising:
generating, by a control module, a control signal wherein the control signal is configured to:
for a given heat demand mode of the heating furnace, operate an induction fan of the heating furnace at more than one fan speed;
in response to a request for a high heat demand mode of the heating furnace, operate the induction fan at a low fan speed during flame ignition within a burner and for a stabilization period after the flame ignition within the burner; and
operate the induction fan at a high fan speed following the stabilization period; and
wherein the low fan speed is less than a higher fan speed designed to support the heating furnace operating at a maximum rated thermal output.

15. The method of claim 14 , further comprising supplying fuel to a burner of the heating furnace at a fuel input rate that is less than a high heat demand mode fuel input rate until an end of the stabilization period.

16. The method of claim 15 , further comprising supplying fuel at the high heat demand mode fuel input rate following the stabilization period.

Assignees

• Lennox Ind Inc

Inventors

• Noman Shiblee S M

Classifications

• F23N2227/02

  Starting or ignition cycles · CPC title

• F23N2233/10

  forcing air through heat exchangers · CPC title

• F23N2237/10

  High or low fire · CPC title

• F23N2233/04

  with variable speed · CPC title

• F23N2237/16

  secondary air · CPC title