Vien, You need to change the orifice from propane to NG. I did mine many years ago, it is a simple matter. In the borrom of the post on mine, there was a little door that you took off, unscrewed the old orifice, and put in the new on. Took about 10 minutes. You might try getting one at Sears or a lawn and garden shop that carries grills. It is about the size of a nickel, a little thicker.