The 3 valves should never be all opened at the same time.
Top and bottom valves open, middle valve closed for normal operation-
top and bottom valves closed, middle valve open for winterizing with water heater having been drained-
2013 Classic 30 Limited
2007 Silver Toyota Tundra Crew Max Limited 5.7 iForce
2006 Vivid Black Harley-Davidson Road King Classic
1999 Black Nissan Pathfinder LE
WBCCI #1811, Region 6, Unit 56