The water heater should be drained if being shut down during freezing temperatures. It is recommended that the tank be drained and flushed every 6 months to remove sediment which may buildup during operation. To drain the tank perform the following steps:
Turn off the power to water heater.
Close the cold water inlet valve and open a nearby hot water faucet.
Connect a hose to the drain valve and terminate it to an adequate drain.
Important: Drain hose should be rated for at least 200°F. If the drain hose does not have this rating, open the cold water inlet valve and open a nearby hot water faucet until water is no longer hot.
Open the water heater drain valve and the nearest hot water faucet. Allow all the water to drain from the tank. Flush the tank with water as needed to remove sediment.
Close the drain valve and refill the tank, and restore power.
If the water heater is going to be shut down for an extended period, the drain valve should be left open.
NOTE: When draining Table Top models, remove the screw securing the drain access cover. Remove the cover by pulling down and away from the water heater