How to Clean the Sediment from Hot Water Heater

We had a minor failure on our water heater recently, leading to a small repair. Looks like it could have been avoided with some minor annual cleaning. Live and learn.

Turn the gas/electric off to the water heater. Leave the cold water supply valve on to the heater. Hook a hose up to the boiler drain on the water heater and turn the valve on. Turn the handle back and forth; there will be grit in the valve assembly and you need to establish good flow before shutting the cold water inlet valve off to the heater.
Once established, shut the cold water inlet valve off. THEN, go around and open all hot side ONLY valves in your home so you can break vaccum and allow the hot water to drain from the tank. That boiler drain off the tank is the lowest point of your potable water system so you need to allow it to drain completely out.
10-25 minutes is the norm for proper draining; you should be able to "shake" the tank to determine it is completely empty. Just because it stops draining does not mean it is empty most times.....usually dirt/debri blocked the pathway to the hose.
Once you are completely sure that the tank is drained, go ahead and turn the cold water inlet valve back on and let the tank drain a bit, then shut it off. "Stomping" on that hose while there is established flow coming out of the hose will purge the tank by a rush of water hitting the bottom and scurrying up the debri to go out of the tank.
Once you've shut the boiler drain to the tank off, LEAVE THE HOT SIDE VALVES OPEN THROUGH THIS ENTIRE PROCESS. So many people think you turn those hot side valves off before filling the tank and that is completely wrong. Air is compressible, water is not. You compress air in your lines you'll end up blowing out faucet aerators next time you go to use the fixtures.
Leave all hot side faucets run until there is a steady flow from all of the faucets without distortion. Once the water is steadily flowing without air, shut the faucets off, turn the electric or gas water heater back on.
It's an hour procedure, maybe an hour and a half, expect around $100-$135 for the procedure.

How to Clean the Sediment from Hot Water Heater? - Plumbing Forum - GardenWeb

Cleaning hot water heater is an easy do it yourself project. All you'll need

is a garden hose, a brush, a pair of plyers or a wrench and some teflon tape.

The bottom of your tank is a catch all for sediment, calcium deposits bacteria and rust. Its a good idea to clean your tank once a year and do a water heater flush every 2 to 3 months.

Your water heater will last years longer. If you have a gas water heater cleaning will help with the noise you hear when the burner is on.

First you'll need to drain the tank. Click here drain water heater if you need help.

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Cleaning Hot Water Heater -How To Clean A Water Heater


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