Abstract: Mobile water heating systems for producing hot water are disclosed herein. In one embodiment, a mobile water heating system includes a water heater having an oval-cylindrical shape. The water heater includes a shell, a lid and a water reservoir having a screen. A first heating coil and a second heating coil can extend between the screen and a first cone and a second cone, respectively. A first burner and a second burner can be configured to mix and combust fuel and air and direct the resulting flames through the heating coils. Pall rings can at least partially fill an interior volume of the water heater and the combustion of the fuel and air can heat the heating coils and the pall rings. Water can be heated by being directed through the heating coils and through a water manifold positioned to spray water on the pall rings.