Water heater:

Draining the water heater will help eliminate any build up of sediment inside the tank, and help keep the water smelling fresh. To drain the tank, first turn down the temperature and let the water in the tank cool for a couple of hours. Turn off the cold water supply, and attach one end of a hose to the bottom drain valve and run the hose to a drain or outside the house. Open a hot water faucet in the house to let air into the top of the tank, and then open the drain valve on the water tank. When all the water has drained from the tank, turn the cold water supply valve off and on a few times, essentially flushing any sediment out of the tank. When the water coming out the drain valve runs clear, disconnect the hose from the drain valve, close the valve and refill the tank. Don't forget to turn off that faucet and turn the thermostat back up.