If the bottom of your water heater fills with sludge, the heater won’t operate at peak performance. Sediment buildup also causes the water at the base of the tank to super-heat and turn to steam, resulting in mini explosions that blast small amounts of sediment off the bottom of the tank.
To clean the sediment out of a water heater, follow these steps:
Unscrew the cold-water supply line at the top of the water heater and remove the nipple screwed into the cold-water port.
Be sure to turn off the power to the water heater and the cold-water inlet valve before you begin any repairs.
Pour a citric-acid-based cleaner into the open hole and wait about eight hours for the acid to dissolve the minerals at the bottom of the tank.
The citric-acid-based cleaning product Mag-Erad works well, but it can sometimes be hard to find at local plumbing supply stores.
Connect a garden hose to the drain valve located at the bottom of the water heater and run the hose out into the garden.
Open the drain valve, reconnect the cold-water supply line, and then turn on the cold-water supply to the water heater.
The cloudy water and sediment that comes out of the end of the hose will amaze you.
When the water runs clear, close the drain valve and remove the hose.
Aside from being a breeding ground for bacteria, sediment at the base of a tank significantly diminishes the efficiency of a gas water heater and can cause it to rumble like a freight train.
Bleed air from the system by turning on the hot-water faucet farthest from the water heater.
When water runs from this faucet, turn it off and repeat this process at other faucets throughout the house.
Turn the power to the water heater back on.
Hopefully, you’ll be in hot water now.