Dual fuel selectable apparatus

Abstract

A heater assembly can be used with a gas appliance. The gas appliance can be a dual fuel appliance for use with one of a first fuel type or a second fuel type different than the first. The heater assembly can include a pressure sensor and a plurality of valves operable by a control module dependent upon a detected fuel pressure. The valves may be solenoid valves that can reduce the available fuel delivery paths to limit fuel delivery to a burner when a higher pressure, such as detection of LP gas, is detected.

What is claimed is: 
     
         1 . A dual fuel heating apparatus comprising:
 a regulator receiving a gas fuel flow;   a first regulator fuel path and a second regulator fuel path through the regulator;   a pressure sensor configured to detect a pressure of the gas fuel flow in the regulator;   a control module in communication with the pressure sensor; and   a regulator valve operable to open or close the second regulator flow path depending on a pressure detected by the pressure sensor.   
     
     
         2 . The dual fuel heating apparatus of  claim 1 , wherein the gas fuel flow is one of a natural gas fuel flow and a propane gas fuel flow. 
     
     
         3 . The dual fuel heating apparatus of  claim 2 , wherein the pressure sensor is a normally open switch, closing when a predetermined pressure is reached. 
     
     
         4 . The dual fuel heating apparatus of  claim 2 , wherein the pressure sensor determines whether the pressure of the gas fuel flow is greater than a predetermined pressure, wherein the predetermined pressure is a pressure greater than a pressure of the natural gas fuel flow and less than or equal to a pressure of the propane gas fuel flow. 
     
     
         5 . The dual fuel heating apparatus of  claim 3 , wherein the regulator valve is a pick and hold solenoid valve. 
     
     
         6 . The dual fuel heating apparatus of  claim 5 , wherein the control module sends a positive output voltage pulse when the pressure exceeds the predetermined pressure to move the solenoid valve from a first position, with the second regulator flow path closed, to a second position, with the second regulator flow path open. 
     
     
         7 . The dual fuel heating apparatus of  claim 5 , further comprising a reset button, wherein the reset button, when depressed, is operable to cause the control module to send a negative output voltage pulse to move the solenoid valve into the first position, with the second regulator flow path closed. 
     
     
         8 . The dual fuel heating apparatus of  claim 1 , further comprising:
 one or more dual fuel gas valves receiving fuel from the regulator, each of the one or more dual fuel gas valves having a first gas valve flow path and a second gas valve flow path for delivering fuel from the regulator to one or more burners; and   a burner valve operable to open or close the second gas valve flow path depending on a pressure detected by the pressure sensor.   
     
     
         9 . The dual fuel heating apparatus of  claim 8 , wherein:
 the gas fuel flow is one of a natural gas fuel flow and a propane gas fuel flow; and   the pressure sensor determines whether the pressure of the gas fuel flow is greater than a predetermined pressure, wherein the predetermined pressure is a pressure greater than a pressure of the natural gas fuel flow and less than or equal to a pressure of the propane gas fuel flow.   
     
     
         10 . The dual fuel heating apparatus of  claim 9 , wherein the control module sends a positive output voltage pulse when the pressure exceeds the predetermined pressure to move the burner valve from a first position, with the second gas valve flow path open, to a second position, with the second gas valve flow path closed. 
     
     
         11 . The dual fuel heating apparatus of  claim 10 , further comprising a reset button, wherein the reset button, when depressed, is operable to cause the control module to send a negative output voltage pulse to move the burner valve into the first position, with the second gas valve flow path open. 
     
     
         12 . A dual fuel heating apparatus comprising:
 a regulator receiving a gas fuel flow;   a pressure sensor configured to detect a pressure of the gas fuel flow in the regulator;   a control module in communication with the pressure sensor;   one or more dual fuel gas valves receiving fuel from the regulator, each of the one or more dual fuel gas valves having a first gas valve flow path and a second gas valve flow path for delivering fuel from the regulator to one or more burners; and   a burner valve operable to open or close the second gas valve flow path depending on a pressure detected by the pressure sensor.   
     
     
         13 . The dual fuel heating apparatus of  claim 12 , wherein:
 the gas fuel flow is one of a natural gas fuel flow and a propane gas fuel flow; and   the pressure sensor determines whether the pressure of the gas fuel flow is greater than a predetermined pressure, wherein the predetermined pressure is a pressure greater than a pressure of the natural gas fuel flow and less than or equal to a pressure of the propane gas fuel flow.   
     
     
         14 . The dual fuel heating apparatus of  claim 13 , wherein the control module sends a positive output voltage pulse when the pressure exceeds the predetermined pressure to move the burner valve from a first position, with the second gas valve flow path open, to a second position, with the second gas valve flow path closed. 
     
     
         15 . The dual fuel heating apparatus of  claim 14 , further comprising a reset button, wherein the reset button, when depressed, is operable to cause the control module to send a negative output voltage pulse to move the burner valve into the first position, with the second gas valve flow path open. 
     
     
         16 . The dual fuel heating apparatus of  claim 15 , wherein the regulator has a first regulator fuel path and a second regulator fuel path through the regulator to pass a fuel flow therethrough, wherein the dual fuel heating apparatus further comprises a regulator valve operable to open or close the second regulator flow path depending on a pressure detected by the pressure sensor. 
     
     
         17 . A dual fuel heating apparatus comprising:
 a regulator receiving a gas fuel flow of either a natural gas fuel flow or a propane gas fuel flow;   a first regulator fuel path and a second regulator fuel path for delivering fuel through the regulator;   a pressure sensor configured to detect a pressure of the gas fuel flow in the regulator;   a control module in communication with the pressure sensor;   a regulator valve operable to open the second regulator flow path when the pressure exceeds a predetermined pressure;   one or more dual fuel gas valves receiving fuel from the regulator, each of the one or more dual fuel gas valves having a first gas valve flow path and a second gas valve flow path for delivering fuel from the regulator to one or more burners; and   a burner valve operable to close the second gas valve flow path when the pressure exceeds the predetermined pressure.   
     
     
         18 . The dual fuel heating apparatus of  claim 17 , wherein the predetermined pressure is a pressure greater than a pressure of the natural gas fuel flow and less than or equal to a pressure of the propane gas fuel flow. 
     
     
         19 . The dual fuel heating apparatus of  claim 17 , wherein the control module sends a positive output voltage pulse when the pressure exceeds the predetermined pressure, the positive output voltage pulse moving the burner valve from a first position, with the second gas valve flow path open, to a second position, with the second gas valve flow path closed, and the positive output voltage pulse moving the regulator valve from a first position, with the second regulator flow path closed, to a second position, with the second regulator flow path open. 
     
     
         20 . The dual fuel heating apparatus of  claim 19 , further comprising a reset button, wherein the reset button, when depressed, is operable to cause the control module to send a negative output voltage pulse to move the burner valve into the first position, with the second gas valve flow path open.