Dual Fuel Vent Free Gas Heater

Abstract

A dual fuel vent free gas heater having at least one gas burner with a plurality of gas outlet ports in an upper surface thereof. The gas outlet ports are in flow communication with at least one pilot flame burner. An adjustable fuel injector or at least two fuel injectors feed fuel to the burner providing for introduction of more than one fuel to the burner. Optionally, an oxygen detection system, manual fuel selection control valve, and/or temperature shut off control system may be incorporated into the dual fuel vent free heater.

1 - 30 . (canceled) 
     
     
         31 . A dual fuel vent free gas heater comprising:
 A main gas burner adapted to receive one of a first type of fuel or a second type of fuel,   a thermal switch in close proximity to the main gas burner; and   a control valve positioned in the fuel flow path proximal to the main gas burner and electrically coupled to the thermal switch, the thermal switch adapted to reoccurringly cause the control valve to shut off the flow of fuel to the main gas burner when the thermal switch detects a temperature indicative that an inappropriate fuel type is being fed to the main gas burner.   
     
     
         32 . A dual fuel vent free gas heater according to  claim 31 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner when the first type of fuel is delivered to the second nozzle. 
     
     
         33 . A dual fuel vent free gas heater according to  claim 31 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner when the first type of fuel is delivered to the second nozzle or the second type of fuel is delivered to the first nozzle. 
     
     
         34 . A dual fuel vent free gas heater according to  claim 32 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         35 . A dual fuel vent free gas heater according to  claim 33 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         36 . A dual fuel vent free gas heater according to  claim 31 , further comprising a pilot burner adjacent the main gas burner, the control valve positioned in the fuel flow path proximal to the pilot burner, the control valve electrically coupled to the thermal switch, the thermal switch causing the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the thermal switch detects a temperature indicative that an inappropriate fuel type is being fed to the main gas burner. 
     
     
         37 . A dual fuel vent free gas heater according to  claim 36 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the first type of fuel is delivered to the second nozzle. 
     
     
         38 . A dual fuel vent free gas heater according to  claim 36 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the first type of fuel is delivered to the second nozzle or the second type of fuel is delivered to the first nozzle. 
     
     
         39 . A dual fuel vent free gas heater according to  claim 37 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         40 . A dual fuel vent free gas heater according to  claim 38 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         41 . A dual fuel vent free gas heater comprising:
 a main gas burner adapted to receive one of a first type of fuel or a second type of fuel,   a thermal switch having a temperature sensor in proximity to the main gas burner; and   a control valve positioned in the fuel flow path proximal to the main gas burner and electrically coupled to the thermal switch, the thermal switch adapted to reocurringly cause the control valve to shut off the flow of fuel to the main gas burner when the temperature sensor of the thermal switch detects a temperature indicative that an inappropriate fuel type is being fed to the main gas burner.   
     
     
         42 . A dual fuel vent free gas heater according to  claim 41 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner when the first type of fuel is delivered to the second nozzle. 
     
     
         43 . A dual fuel vent free gas heater according to  claim 41 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner when the first type of fuel is delivered to the second nozzle or the second type of fuel is delivered to the first nozzle. 
     
     
         44 . A dual fuel vent free gas heater according to  claim 42 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         45 . A dual fuel vent free gas heater according to  claim 43 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         46 . A dual fuel vent free gas heater according to  claim 41 , further comprising a pilot burner adjacent the main gas burner, the control valve positioned in the fuel flow path proximal to the pilot burner, the control valve electrically coupled to the thermal switch, the thermal switch causing the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the temperature sensor detects a temperature indicative that an inappropriate fuel type is being fed to the main gas burner. 
     
     
         47 . A dual fuel vent free gas heater according to  claim 46 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the first type of fuel is delivered to the second nozzle. 
     
     
         48 . A dual fuel vent free gas heater according to  claim 46 , comprising a first nozzle positioned at an inlet of the main gas burner to deliver the first type of fuel to the main gas burner and a second nozzle positioned at the inlet of the main gas burner to deliver the second type of fuel to the main gas burner, the thermal switch adapted to cause the control valve to shut off the flow of fuel to the main gas burner and pilot burner when the first type of fuel is delivered to the second nozzle or the second type of fuel is delivered to the first nozzle. 
     
     
         49 . A dual fuel vent free gas heater according to  claim 47 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas. 
     
     
         50 . A dual fuel vent free gas heater according to  claim 48 , wherein the first type of gas is liquid propane gas and the second type of fuel is natural gas.