Houses in foreclosure often go through a winterization process to protect the pipes from freezing. Especially in unoccupied foreclosed houses, this process sometimes extends to year-round. When you buy a house that has been in foreclosure, turning the water back on properly, or dewinterizing the house, protects the pipes from damage. You can hire a plumber for this job, or you can do it yourself. Although some banks pay for the dewinterization of a foreclosed home, most do not, according to Sarah Stelmok of Champion Homes Realty.
Remove the aerators from the kitchen and bathroom sinks before turning on the water in the house. This allows any mineral buildup to pass through and not get stuck in the aerator. Check that every faucet is turned off before turning on the water valves.
Turn on the water supply valves under each sink. The supply valves are knobs located on the pipes under the sink. Turn the valves counter-clockwise, or to the left, to open them. Open the valve on your hot water heater as well.
Locate an outside water faucet close to the water meter. Turn this to on so that water flows from it when you turn on the main water supply; this way you know that you have water going to the house.
Locate the main water valve on the water meter. It probably looks like a lever you can rotate to the left to open. Rotate the valve a quarter turn, wait 20 seconds, and rotate another quarter turn. Repeat until the valve is completely open. It is important to open the main valve slowly so that the pipes in your house aren't flooded with full-power water, which can cause leaking.
Check that water is flowing through the exterior faucet. If it is, turn the faucet off. Go inside and listen for water flowing into the hot water tank. Do not turn on the electricity to the hot water heater until the tank is full of water.
Turn the water faucet on at each sink. Do this slowly, and allow each faucet to run for 15 or 20 seconds. As you turn off the water, replace the aerators. Once you've cleared each sink, turn the valves for the toilets a quarter turn at a time until they are fully open and the tanks are filling with water. When they are full, flush the toilets. Run water into each shower and bathtub as well. When testing the different water outlets for the first time, go slowly so the pipes have time to adjust to the water and won't leak.
Turn off all the water outlets once the hot water tank is full. Check the water meter. If the usage meter is rotating, you may have a leak. In this instance, call a plumber. You also can do a visual tour of the inside and outside of your house to check for any leaking water.