In certain embodiments, a valve assembly includes a housing. The housing can define a first fuel input and a second fuel input. The housing can further define a first flow path, a second flow path, a third flow path, and a fourth flow path. The assembly can include a fluid flow controller configured to selectively permit fluid communication between the first fuel input and either the first flow path or the second flow path, and configured to selectively permit fluid communication between the second fuel input and either the third flow path or the fourth flow path. The assembly can further include a first nozzle member defining an inlet and an outlet. The inlet of the first nozzle member can be in fluid communication with the first flow path. The assembly can further include a second nozzle member defining an inlet and an outlet. The inlet of the second nozzle member can be in fluid communication with the second flow path.