2018 forest river Rockwood 1940ltd. I've looked in the manual and no success. I see the hose coming out underneath the pup but can't find the knob to release the water stored in my fresh water holding tank. I've read it could possibly be under the dinette where my tank is stored. Before I jack it up and take the screws off the panel(from what I remember there were) does anyone know this to be true?