Draining sediment from "self cleaning" hot water tanks

[lairdwd]

You all have seen them by now. They are sold everywhere - the supposid "self cleaning" hot water heater.

I just bought the house I'm living in, and I know the previous owner wasn't draining the tank at all. Anybody have any thoughts if this should be done regardless of self cleaning or not?

[jadnashua]

Those tanks try to swirl th ewater and keep the crud deposits in suspension. Trouble is, the outlet is at the top, and they try to sink. You need a very strong flow for awhile, but even then, it probably won't cause enough to flow out. Drain it manually, if you are so inclined...that works better, but it may not make that much difference one way or the other if it hasn't been done for awhile.

[Mikey]

I'd rather have the crud settle out than be distributed through the house, even if the swirl technique did work. The only benefit I can see from the "self cleaning" models is that the swirling water will keep the crud in suspension while you're flushing the tank -- otherwise there might not be enough turbulence to lift the accumulated crud off the bottom of the tank. I flush mine every 6 months and zap it with the pressure washer when I'm feeling especially ambitious.

[master plumber mark]

self cleaning water heaters is a little white lie

made up and told by all the water heater comanies

to get people to buy their brand

its a bell and whistle that does not work


their is no such thing as a self cleaning water heater.....


Purdue did a study in the 90s that proved none of them did much
of anything they claimed that they did.....


just get a good name brand when you buy one and simply put a garden
hose to the bottom faucet every 6 months
and run it full blast for about 2 minutes

and then you have "self cleaned " your water heater

[hj]

You need an unrestricted flow to have enough volume to make the self cleaning feature work, and the only two items that have that are the bathtub and the clothes washer. But that only stirs the material off the bottom of the tank. Then you need a continuous flow for enough time so that the material can be carried from the bottom of the tank to the top and then out into the piping. In other words, it will seldom happen, so if you are concerned about accumulation, drain the tank manually.

[master plumber mark]

Very seldom will this self cleaning feature ever work like they claim it will.......



The thing that is stopping it from working properly is

called "Newtons Law of Gravity"


you cant force sand to float upwards 4 feet in a tank of
water from the bottom...

and expect it to be sucked out hot outlet and into the
plumbing system

[plumber1]

My experience tells me that draining water heaters is usually a waste of time and not much gets accomplished.

[hj]

How did they "make up the self cleaning thing", and HOW do you know it is working very well?