How to keep the constant temperature of liquefied gas water heater?

You adjust the fire power of the water heater to the lowest and the temperature to the highest, winter and summer. Then boil the water, test the water temperature, use it if it can, and turn down the temperature if it is too high. If it is low, adjust the firepower. Until it's just the temperature for a bath. When adjusting the temperature, try to move only one, which will be much better. Finally, Supor does not produce gas water heaters.