Dual fuel valve

A method of controlling a flow of fuel comprising:

• receiving the fuel at a gas judgment assembly including a nozzle sized to permit an existence of a flame when liquid propane flows through the nozzle, but prevent the existence of the flame when natural gas flows through the nozzle, and further configured to sense the existence of the flame with a sensor;
• providing an electrical current by a natural gas thermocouple when heated;
• receiving the electrical current at a solenoid valve electrically coupleable to the natural gas thermocouple, the solenoid valve configured to open and allow a passage of fuel when provided with the electrical current, and remain closed when not provided with the electrical current;
• and
• controlling a relay by a control system electrically coupled to the gas judgment assembly, the control system configured to keep the relay in a closed state absent a signal from the gas judgment assembly indicating the existence of a flame, and further configured to open the relay when the control system receives the signal from the gas judgment assembly, wherein the relay electrically couples the natural gas thermocouple to the solenoid valve when closed, and electrically disconnects the natural gas thermocouple to the solenoid valve when opened.