I'm not sure where the valve is located in your model. Look inside cabinets or under furniture for a valve that is down low near or below the floor - maybe close to the tank itself. There are probably other valves for draining the rest of the plumbing as well that may be open. Hopefully someone familiar with your model year will chime in with the location. Good luck.
Cameron & the Labradors, Kai & Samm
North Vancouver, BC
Live! Life's a banquet and most poor suckers are starving to death! - Mame Dennis