How much good does it do to drain your WH?

I decided, for the first time in years, to drain my 2 50-gal water heaters. After the water stopped draining, I turned on the water supply for a few seconds, and the 1st WH put out a good deal of small white sediment particles. After it finished draining again, I repeated this about 5 times. I then did the same with the 2nd tank (once the first one filled up).

It got me to thinking, though, that I wonder if it's really necessary to drain the whole tank? Could we, instead, just open the drain valve while the water supply is still open, and flush out the bottom of the tank? Or is it really necessary to have the tank empty?

Or does any of this do any real good?

tank

When you open the drain valve, the only material washed out is what is in its vicinity. Draining the tank does not do much different. The majority of the offending material will still be on the bottom of the tank regardless of which method you use, unless you remove the drain valve and use a wire to pull the stuff out, and even that would be very labor intensive, and only slightly more effective.

I usually install full port drain valves on water heaters I provide and install. Around here, if you power flush the tank every couple of months it's a good thing. The crummy plastic valves are a joke and the brass valves open up the size of a pea. Good luck trying drain them when the w.h. finally rolls craps 7.

heater

When that happens you take it out into the driveway and snap the plastic valve off.

Not if it is an 80 gallon in a finished basement your not.

For situations like this I have a pump set up. I pull the dielectric and insert a tube that reaches to near the bottom and the pump empties the tank in about 10-15 min or so depending on tank size.

My son-in-law recently told me his WH was not supplying as much hot water as it had in the past, and we talked about various possibilities I have learned about here. He ultimately discovered sediment smothering (completely covering) his single electric heating element.

About once a month or so, I connect a short piece of water hose to my electric WH's plastic drain valve and let whatever comes out run into the nearby sump for a couple of minutes. But the first time I ever did that, I ran the hose outside and could still feel chucks coming out for about an hour.

When I replaced an old WH a few years ago I opened it up just for fun. The bottom foot or so was solid muck of some kind. I didn't show it to my wife...

I just drained a few gallons out of my current WH and a few white crystals came out; water was clear. Next time I replace the anode rod I think I'll stick my pressure washer in there.