There are several things that you can do to improve the performance and longevity of a water heater. The fact that your utility bill is high, and that you are having trouble maintaining hot water, are no doubt related.

First, it's a good idea to drain the water heater at least once annually-twice annually in areas with higher-mineral-content water. This will prevent the accumulation of sediment at the bottom of the tank, a problem that greatly inhibits the effectiveness of the gas burners below.

An electric water heater also will benefit from this periodic maintenance, because once drained, you can remove the heating elements and clean any debris that has accumulated on them. It is not unusual for the heating element to corrode and become nonfunctional.

Draining the water heater is a relatively simple task that generally doesn't require any tools. Start by turning off the gas or electricity to the appliance, and close the cold water valve at the top of the tank. Connect a garden hose to the drain valve at the bottom of the tank, and open the valve a couple of turns. You also will want to open at least one hot water faucet somewhere in the house. This will let air into the tank and help it drain. Once the tank is empty, turn on the cold water valve at the top of the tank and close the drain valve (after water from the drain appears clear). The faucet that was opened when draining should remain open allowing air to escape until water comes rushing out of it. Disconnect the hose and restore power to the unit.