Mine is under the stove top behind the drawer. To remove the drawer open it and there are little plastic pieces in the slide. Push one down the other up. I have a 29xk. Find the water heater outside and go inside and see if there is a drawer or something you must take out to get to it
Is that an affirmative that you did find it there?
My kitchen sink is immediately above the outside heater, and there is a panel below the sink with an open top. I will use a mirror to see if I can locate it behind there before taking it apart. Thanks!