Hi M.,
My son, now 3yo, also slept with noise of all types while he was a baby. We did white noise, a fan, and sometimes music. He had reflux, so we did whatever would work. Now, at 3, he can sleep without the fan with no problem. We usually still run one on low, barely noticeable just to circulate air in his room (it gets too warm in his room). But I was surprised that for a little boy that would not sleep at 1yr without his noise, and he would wake up if I walked in and made any noise.... now I can walk in, turn on the light, make noise... he is OUT.
My husband thought he would be hooked on the fan, but he'll sleep fine without it. My daughter is 16mos and she sleeps with a fan to drown out the noise of the 3yo.... I hope she will also out grow it. She'll still wake up if I walk in b/c the door makes a "pop" noise. We'll see... But I wouldn't worry about it. I just do what works for the time and realized that they change so much and their needs change. Good luck and enjoy his nap times while you have them!