Chances are this is related to sediment build up. A flush of the water heater may be all that is required.
Follow these steps to flush your water heater:
CAUTION: The water in the water heater is very hot. Use extreme caution and keep children and pets away from the area when flushing the water heater.
- Attach a garden hose to the drain valve (looks like a hose bibb) at the bottom of the heater. Run the garden hose either outside or to the nearest drain.
- Open the drain valve, which will allow the water to drain through the hose.
- When the water is running clear (usually after about 20 minutes), close the drain valve and remove the hose.
- Turn on a hot water faucet in your home and let it run until all air bubbles are out of the line, then turn it off.