Abstract: Systems and methods for hot refueling from a fuel source to one or more fuel tanks associated with equipment in the hot zone of a well site. Automatic valves are located at the fuel tanks, obviating the need for electronic communication in or out of the hot zone. A flexible conduit or hose is connected between one or more outlet ports of the fuel source to corresponding one or more automatic valves at the fuel tanks. The valve, such as a float-type valve, uses fuel level to open the valve whenever the fuel tank is below a full fuel level threshold. Fuel levels at or above the full fuel level threshold automatically close the valve.