There should be a second set of valves. One on a line going into the lower part of your tank (cold water), a second on a line coming out of upper part of your tank (hot water) and a third located on a line that connects the two (bypass). The cold and hot valves need to be opend (parallel to the line) and the bypass should be closed (perpendicular to the line). These valves are usually located towards the rear of the tank. Turn the valves just the opposite to winterize.
Hope this helps.
Gary & Trish
"PT Crew Member Since 11/2010"
2017 Prime Time Crusader 315RST TE 6.0 : 2007 Flagstaff 206ST MAC Series
2012 F-250 Lariat : FX4 : CC : SB : 6.7L Diesel : 3/55 Gears
2016 Nights Camped - 9