Heating assembly

Abstract

A safety pilot can be used with a gas appliance. The gas appliance can be a single fuel or a dual fuel appliance for use with one of a first fuel type or a second fuel type different than the first. The safety pilot can include a first thermocouple, a second thermocouple, and one or more nozzles configured to direct combusting fuel towards both the first and second thermocouples.

What is claimed is: 
     
         1 . A safety pilot, comprising:
 one or more pilot nozzles, each of the one or more pilot nozzles having an outlet;   a first thermocouple positioned in alignment with the outlet of at least one of said one or more pilot nozzles, said first thermocouple comprising a first anode and a first cathode and configured to generate voltage in response to heat from the at least one of said one or more pilot nozzles having an outlet aligned with the first thermocouple;   a second thermocouple positioned in alignment with the outlet of at least one of said one or more pilot nozzles, said second thermocouple comprising a second anode and a second cathode and configured to generate voltage in response to heat from said at least one of said one or more pilot nozzles having an outlet aligned with the second thermocouple;   said second cathode being in electrical contact with said first anode, said second anode being in electrical contact with said first cathode, such that when a single thermocouple is heated in response to heat from said one or more pilot nozzles a first current is generated by the safety pilot and when both the first and the second thermocouples are heated in response to heat from said one or more pilot nozzles, two currents are generated which combine to generate a second current that is less than the first current.   
     
     
         2 . The safety pilot of  claim 1 , further comprising an igniter. 
     
     
         3 . The safety pilot of  claim 1 , wherein said one or more pilot nozzles comprises a first pilot nozzle and a second pilot nozzle. 
     
     
         4 . The safety pilot of  claim 3 , further comprising a bracket, wherein said first pilot nozzle and said second pilot nozzle are mounted to said bracket. 
     
     
         5 . The safety pilot of  claim 3 , wherein the first pilot nozzle has a first air inlet that is larger than a second air inlet of the second pilot nozzle. 
     
     
         6 . The safety pilot of  claim 3 , wherein the outlet of the first pilot nozzle is in alignment with the first thermocouple and the outlet of the second pilot nozzle is in alignment with the second thermocouple. 
     
     
         7 . The safety pilot of  claim 6 , wherein the first pilot nozzle and the second pilot nozzle are part of a housing configured to receive a flow of fuel, wherein the housing is configured such that a first portion of the flow of fuel passes through the first pilot nozzle and a second portion of the flow of fuel passes through the second pilot nozzle. 
     
     
         8 . The safety pilot of  claim 6 , wherein a minimum cross-sectional area of a flow path through the first nozzle is different from a minimum cross-sectional area of a flow path through the second nozzle. 
     
     
         9 . The safety pilot of  claim 6 , wherein said one or more pilot nozzles comprises a third pilot nozzle having an outlet in alignment with the first thermocouple. 
     
     
         10 . The safety pilot of  claim 3 , wherein the outlet of the first pilot nozzle is in alignment with the first thermocouple and the second thermocouple, and the outlet of the second pilot nozzle is in alignment with the first thermocouple. 
     
     
         11 . A heater assembly, comprising:
 one or more pilot nozzles, each of said one or more pilot nozzles having an outlet;   a first thermocouple aligned with the outlet of at least one of said one or more pilot nozzles, said first thermocouple generating voltage in response to heat from said at least one of said one or more pilot nozzles having an outlet aligned with the first thermocouple;   a second thermocouple aligned with the outlet of at least one of said one or more pilot nozzles, said second thermocouple generating voltage in response to heat from said at least one of said one or more pilot nozzles having an outlet aligned with the second thermocouple, said first thermocouple in electrical contact with said second thermocouple; and   an electrically responsive valve in electrical communication with said first thermocouple and said second thermocouple, wherein (1) said valve is closed when insufficient signal is generated by said first thermocouple and no significant signal is generated by said second thermocouple; (2) said valve opens in response to a first signal level from said first thermocouple when no or insufficient signal is generated by said second thermocouple and (3) said valve closes in response to said first signal level from said first thermocouple and a sufficient signal level from said second thermocouple.   
     
     
         12 . The heater assembly of  claim 11 , with said first thermocouple comprising a first anode and a first cathode and said second thermocouple comprising a second anode and a second cathode, said second cathode being in electrical contact with said first anode, said second anode being in electrical contact with said first cathode. 
     
     
         13 . The heater assembly of  claim 12 , further comprising an igniter. 
     
     
         14 . The heater assembly of  claim 12 , wherein said one or more pilot nozzles comprises a first pilot nozzle and a second pilot nozzle. 
     
     
         15 . The heater assembly of  claim 11 , wherein said one or more pilot nozzles comprises a first pilot nozzle and a second pilot nozzle. 
     
     
         16 . The heater assembly of  claim 15 , wherein the first pilot nozzle has a first air inlet that is larger than a second air inlet of the second pilot nozzle. 
     
     
         17 . The heater assembly of  claim 15 , wherein the first pilot nozzle and the second pilot nozzle are part of a housing configured to receive a flow of fuel, the housing further configured such that the first pilot nozzle receives a first portion of the flow of fuel and the second pilot nozzle receives a second portion of the flow of fuel. 
     
     
         18 . The heater assembly of  claim 17 , wherein the first pilot nozzle is configured to produce a flame of a first size and the second pilot nozzle is configured to produce a flame of a second size different from the first size. 
     
     
         19 . The heater assembly of  claim 15 , wherein the outlet of the first pilot nozzle is in alignment with the first thermocouple and the outlet of the second pilot nozzle is in alignment with the second thermocouple. 
     
     
         20 . The heater assembly of  claim 15 , wherein the outlet of the first pilot nozzle is in alignment with the first thermocouple and the second thermocouple, and the outlet of the second pilot nozzle is in alignment with the first thermocouple. 
     
     
         21 . The heater assembly of  claim 15 , further comprising a bracket, wherein said first pilot nozzle and said second pilot nozzle are mounted to said bracket. 
     
     
         22 . The heater assembly of  claim 11 , wherein the electrical contact between said first thermocouple and said second thermocouple is such that a voltage from the second thermocouple reduces the current that would be generated by a voltage from said first thermocouple, in the absence of voltage from the second thermocouple.