If you have 'water panel' check position of 'winterize' switch/valve
If no wet bay then check backside of water heater for valving
Depending on which set up you have....1 valve, 2 valve or 3 valve
Cold water goes in bottom of WH
Bypass connects cold & hot water lines
Hot outlet comes out top of WH
Cold inlet-----OPEN
Bypass---------CLOSE
HOT outlet-----OPEN
Cold can be single valve, bypass single valve, hot single valve (3 valve)
Cold can be single, bypass single, hot no valve (check valve in out)---(2 valve)
Cold/bypass can be 3-way valve, hot/bypass a 3-way (2 valve)
Cold/bypass can be 3-way, hot out no valve (check valve in out)---(1 valve)