How To Turn Off Gas Water Heater For Vacation. Draining it will prevent a problem if a leak did occur. It could take you 30 years or more to break even, since the tankless water heater would sit idle in your vacation home for so many days each year.
For electric water heaters, turn off. You may hear a slight hiss. Also, when you turn off your water heater when on a vacation, you only meet more problems.
If electric water heater just to he on the safe side, disconnect it from the wall (ac).
Standard natural gas water heater in general, if you have a standard natural gas water heater (connected to a chimney), it is very easy to switch it to “vacation” mode: Turn down the thermostat while you're away, but don't turn off the furnace completely, which could put your pipes in danger of freezing. Should you turn off your water heater when not in use? Also, when you turn off your water heater when on a vacation, you only meet more problems.