You cannot completely eliminate the chance of a leak developing while you’re gone, but here are a few things you can do to minimize the chances of coming home to a mess.
Laundry – Completely turn off both the hot and cold water valves that supply your washing machine with water. The hoses connecting your washing machine to the water supply valves are one of the most notorious places for a major failure. That 5 gallons per minute we talked about earlier? This is where that could happen.
Hose bibbs (your outside spigots) – Make sure they are completely turned off and all hoses are disconnected.
Water heater – Turn off the valve that supplies the water to the water heater. In the event of a water heater failure, you will only lose the contents of the water heater, rather than several gallons of water per minute flowing out of the water heater for the entire time you are gone. Also, there’s no point in keeping water hot if you aren’t going to be home, right? If you have a gas water heater, you can generally just turn the temperature control to, “Vacation”. If you have an electric water heater, you just turn the breaker off at your electrical panel.
Garbage disposal – This is more about cleanliness than stopping a plumbing failure but cleaning out your garbage disposal with about a half a cup of vinegar before leaving to avoid coming home to a stinky kitchen.
Toilet – Again, this is more about keeping things clean. Pour a half a cup of chlorine in the bowl (not the tank) to keep a ring from developing around the rim. And be sure to close the lid to keep any pets from drinking the water.
Get these things done and you can have yourself a great and relaxing vacation!