CA2547102A1 - Low power control system and associated methods for a water heater with flammable vapor sensor - Google Patents
Low power control system and associated methods for a water heater with flammable vapor sensor Download PDFInfo
- Publication number
- CA2547102A1 CA2547102A1 CA002547102A CA2547102A CA2547102A1 CA 2547102 A1 CA2547102 A1 CA 2547102A1 CA 002547102 A CA002547102 A CA 002547102A CA 2547102 A CA2547102 A CA 2547102A CA 2547102 A1 CA2547102 A1 CA 2547102A1
- Authority
- CA
- Canada
- Prior art keywords
- fuel
- electrical
- thermoelectric
- heating apparatus
- fired heating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N5/00—Systems for controlling combustion
- F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
- F23N5/10—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using thermocouples
- F23N5/102—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using thermocouples using electronic means
Abstract
A transistor used as a normally open switch is connected in the millivolt electrical circuit of a fuel-fired natural draft water heater in series with a thermopile device impinged upon by a standing pilot flame, and the solenoid coil portion of the pilot fuel valve. A variable resistance type flammable vapor sensor is connected in a control circuit which is powered by a DC battery and is coupled only to the transistor portion of the millivolt circuit. In the absence of flammable vapor detection by the sensor the control circuit outputs an electrical signal to the transistor that holds it in a closed position to thereby maintain the standing pilot flame.
In response to sensor detection of flammable vapor, the control circuit output signal terminates to cause the transistor to return to its normally open switch position, thereby shutting off the pilot flame.
In response to sensor detection of flammable vapor, the control circuit output signal terminates to cause the transistor to return to its normally open switch position, thereby shutting off the pilot flame.
Claims (23)
1. Fuel-fired heating apparatus comprising:
a burner adapted to receive fuel and combustion air and create a flame therefrom;
a normally closed fuel valve coupled to said burner for supplying fuel thereto when opened;
a thermoelectric circuit having connected in series therein (1) a thermoelectric device positioned to receive heat from said flame and responsively generate an electrical voltage, (2) a solenoid structure operative to receive electrical power from said thermoelectric device and responsively hold said normally closed fuel valve in an open position, and (3) a normally open switch device; and a low power electrical control circuit, operable by an electrical power source and coupled to said thermoelectric circuit only via said normally open switch device, for protecting said heating apparatus against an undesirable operating condition, said low power electrical control circuit having connected therein a variable resistance sensor operative to detect said undesirable operating condition, said control circuit, in the absence of detection by said sensor of said undesirable operating condition, outputting an electrical signal to said switch device to maintain it in a closed state, and terminating said electrical signal upon detection by said sensor of said undesirable operating condition to return said switch device to its normally open state.
a burner adapted to receive fuel and combustion air and create a flame therefrom;
a normally closed fuel valve coupled to said burner for supplying fuel thereto when opened;
a thermoelectric circuit having connected in series therein (1) a thermoelectric device positioned to receive heat from said flame and responsively generate an electrical voltage, (2) a solenoid structure operative to receive electrical power from said thermoelectric device and responsively hold said normally closed fuel valve in an open position, and (3) a normally open switch device; and a low power electrical control circuit, operable by an electrical power source and coupled to said thermoelectric circuit only via said normally open switch device, for protecting said heating apparatus against an undesirable operating condition, said low power electrical control circuit having connected therein a variable resistance sensor operative to detect said undesirable operating condition, said control circuit, in the absence of detection by said sensor of said undesirable operating condition, outputting an electrical signal to said switch device to maintain it in a closed state, and terminating said electrical signal upon detection by said sensor of said undesirable operating condition to return said switch device to its normally open state.
2. The fuel-fired heating apparatus of Claim 1 wherein:
said fuel-fired heating apparatus is a water heater.
said fuel-fired heating apparatus is a water heater.
3. The fuel-fired heating apparatus of Claim 1 wherein:
said burner is a pilot burner.
said burner is a pilot burner.
4. The fuel-fired heating apparatus of Claim 1 wherein:
said thermoelectric device is a thermopile structure.
said thermoelectric device is a thermopile structure.
5. The fuel-fired heating apparatus of Claim 1 wherein:
said normally open switch device is a normally open solid state switch device.
said normally open switch device is a normally open solid state switch device.
6. The fuel-fired heating apparatus of Claim 5 wherein:
said normally open solid state switch device is a field effect transistor.
said normally open solid state switch device is a field effect transistor.
7. The fuel-fired heating apparatus of Claim 1 wherein:
said electrical power source is a non-thermoelectric electrical power source.
said electrical power source is a non-thermoelectric electrical power source.
8. The fuel-fired heating apparatus of Claim 7 wherein:
said non-thermoelectric electrical power source is a DC battery.
said non-thermoelectric electrical power source is a DC battery.
9. The fuel-fired heating apparatus of Claim 1 wherein:
neither of said thermoelectric circuit and said low power electrical control circuit is operative to receive an electrical current flow from the other of said thermoelectric circuit and said low power electrical control circuit.
neither of said thermoelectric circuit and said low power electrical control circuit is operative to receive an electrical current flow from the other of said thermoelectric circuit and said low power electrical control circuit.
10. The fuel-fired heating apparatus of Claim 1 wherein:
said variable resistance sensor is a flammable vapor sensor.
said variable resistance sensor is a flammable vapor sensor.
11. The fuel-fired heating apparatus of Claim 1 wherein:
said low power electrical control circuit further includes a multi-resistor bridge section, and said variable resistance sensor forms a resistive portion of said bridge section.
said low power electrical control circuit further includes a multi-resistor bridge section, and said variable resistance sensor forms a resistive portion of said bridge section.
12. The fuel-fired heating apparatus of Claim 11 wherein:
said low power electrical control circuit further includes an operational amplifier having an input portion operatively connected across said bridge section, and an output portion coupled to said normally open switch device.
said low power electrical control circuit further includes an operational amplifier having an input portion operatively connected across said bridge section, and an output portion coupled to said normally open switch device.
13 13. The fuel-fired heating apparatus of Claim 12 wherein:
said operational amplifier is an open collector output type operational amplifier.
said operational amplifier is an open collector output type operational amplifier.
14. The fuel-fired heating apparatus of Claim 13 wherein:
said low power electrical control circuit further includes a first electrical lead interconnecting said output portion of said operational amplifier to said normally open switch device, a second electrical lead interconnected between said first electrical lead and said bridge section, and a pull-up resistor connected in said second electrical lead.
said low power electrical control circuit further includes a first electrical lead interconnecting said output portion of said operational amplifier to said normally open switch device, a second electrical lead interconnected between said first electrical lead and said bridge section, and a pull-up resistor connected in said second electrical lead.
15. A method of inhibiting extraneous flammable vapor ignition by a fuel-fired heating appliance having a burner adapted to receive fuel and combustion air and create a flame therefrom, a normally closed fuel valve coupled to said burner for supplying fuel thereto when opened, a thermoelectric circuit having connected in series therein a thermoelectric device positioned to receive heat from said flame and responsively generate an electrical voltage, and a solenoid structure operative to receive electrical power from said thermoelectric device and responsively hold said normally closed fuel valve in an open position, said method comprising the steps of:
installing a normally open switch device in said thermoelectric circuit in series with said thermoelectric device and said solenoid structure;
providing a low power electrical control circuit having an electrical power source and a variable resistance type gas sensor incorporated therein, said control circuit having an output portion operative to create and maintain an electrical output signal in the absence of said sensor being exposed to a predetermined concentration of a gas, and to terminate said electrical signal when said sensor is exposed to at least said predetermined concentration of the gas; and coupling said output portion to said thermoelectric circuit, only via said normally open switch device so that the resistance of said sensor is not present in said thermoelectric circuit, in a manner such that said normally open switch is closed during the presence of said electrical signal, and is open in the absence of said electrical signal.
installing a normally open switch device in said thermoelectric circuit in series with said thermoelectric device and said solenoid structure;
providing a low power electrical control circuit having an electrical power source and a variable resistance type gas sensor incorporated therein, said control circuit having an output portion operative to create and maintain an electrical output signal in the absence of said sensor being exposed to a predetermined concentration of a gas, and to terminate said electrical signal when said sensor is exposed to at least said predetermined concentration of the gas; and coupling said output portion to said thermoelectric circuit, only via said normally open switch device so that the resistance of said sensor is not present in said thermoelectric circuit, in a manner such that said normally open switch is closed during the presence of said electrical signal, and is open in the absence of said electrical signal.
16. The method of Claim 15 wherein:
said fuel-fired heating appliance and said thermoelectric circuit are existing apparatus, and said method is performed as a retrofit method in which said low power electrical control circuit and normally open switch device are operatively coupled to the existing thermoelectric circuit.
said fuel-fired heating appliance and said thermoelectric circuit are existing apparatus, and said method is performed as a retrofit method in which said low power electrical control circuit and normally open switch device are operatively coupled to the existing thermoelectric circuit.
17. The method of Claim 15 wherein:
said installing step is performed using a solid state switch.
said installing step is performed using a solid state switch.
18. The method of claim 15 wherein:
said installing step is performed using a field effect transistor.
said installing step is performed using a field effect transistor.
19. The method of claim 15 wherein:
said providing step includes the step of using a DC battery as said electrical power source.
said providing step includes the step of using a DC battery as said electrical power source.
20. The method of Claim 15 wherein:
said providing step is performed using a flammable vapor sensor as said variable resistance type gas sensor.
said providing step is performed using a flammable vapor sensor as said variable resistance type gas sensor.
21. The method of Claim 15 wherein:
said providing step includes the step of incorporating said gas sensor as a resistive portion of a multi-resistor bridge section of said low power electrical control circuit.
said providing step includes the step of incorporating said gas sensor as a resistive portion of a multi-resistor bridge section of said low power electrical control circuit.
22. The method of Claim 21 wherein:
said providing step includes the step of connecting the output side of an operational amplifier across said bridge section, and said coupling step is performed by electrically connecting the output side of said operational amplifier to said normally open switch device.
said providing step includes the step of connecting the output side of an operational amplifier across said bridge section, and said coupling step is performed by electrically connecting the output side of said operational amplifier to said normally open switch device.
23. The method of Claim 22 wherein:
said operational amplifier is an open collector output type operational amplifier, said coupling step includes the step of connecting a first electrical lead between said output side of said operational amplifier and said normally open switch device, and said providing step includes the steps of interconnecting a second electrical lead between said first electrical lead and said bridge section, and connecting a pull-up resistor in said second electrical lead.
said operational amplifier is an open collector output type operational amplifier, said coupling step includes the step of connecting a first electrical lead between said output side of said operational amplifier and said normally open switch device, and said providing step includes the steps of interconnecting a second electrical lead between said first electrical lead and said bridge section, and connecting a pull-up resistor in said second electrical lead.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11/143,833 | 2005-06-02 | ||
| US11/143,833 US20060275720A1 (en) | 2005-06-02 | 2005-06-02 | Low power control system and associated methods for a water heater with flammable vapor sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2547102A1 true CA2547102A1 (en) | 2006-12-02 |
| CA2547102C CA2547102C (en) | 2009-12-22 |
Family
ID=37480417
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002547102A Expired - Fee Related CA2547102C (en) | 2005-06-02 | 2006-05-16 | Low power control system and associated methods for a water heater with flammable vapor sensor |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US20060275720A1 (en) |
| AU (1) | AU2006202232B2 (en) |
| CA (1) | CA2547102C (en) |
| NZ (1) | NZ547566A (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7032542B2 (en) * | 2004-06-08 | 2006-04-25 | Emerson Electric Co. | Apparatus and methods for controlling a water heater |
| US7372005B2 (en) | 2004-09-27 | 2008-05-13 | Aos Holding Company | Water storage device having a powered anode |
| US7806683B2 (en) * | 2006-08-04 | 2010-10-05 | Orkli, S. Coop | Safety valve supply circuit for the ignition of a gas burner |
| US20090004612A1 (en) * | 2007-06-28 | 2009-01-01 | Therm-O-Disc, Incorporated | Gas-Fired Heating Appliance Having a Flammable Vapor Sensor Control Device |
| CA2619075A1 (en) | 2007-08-28 | 2009-02-28 | Aos Holding Company | Appliance having a safety string |
| US9080769B2 (en) | 2011-08-11 | 2015-07-14 | Emerson Electric Co. | Apparatus for indicating level of pilot flame output |
| EP2872828B1 (en) * | 2012-07-16 | 2019-12-04 | Bromic Pty Limited | Gas heater |
| US9546786B2 (en) * | 2012-11-30 | 2017-01-17 | Field Controls, Llc | Self-powered damper system |
| US11331019B2 (en) | 2017-08-07 | 2022-05-17 | The Research Foundation For The State University Of New York | Nanoparticle sensor having a nanofibrous membrane scaffold |
| US11908618B2 (en) * | 2019-12-19 | 2024-02-20 | Orkli, S. Coop. | Thermoelectric assembly for powering electromagnetic valves of a cooking appliance |
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-
2005
- 2005-06-02 US US11/143,833 patent/US20060275720A1/en not_active Abandoned
-
2006
- 2006-05-16 CA CA002547102A patent/CA2547102C/en not_active Expired - Fee Related
- 2006-05-26 AU AU2006202232A patent/AU2006202232B2/en not_active Ceased
- 2006-05-30 NZ NZ547566A patent/NZ547566A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CA2547102C (en) | 2009-12-22 |
| AU2006202232A1 (en) | 2006-12-21 |
| US20060275720A1 (en) | 2006-12-07 |
| NZ547566A (en) | 2007-10-26 |
| AU2006202232B2 (en) | 2008-01-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |