Black precipitate in hot water

There is a "sacrificial anode" inside of a hot water tank, electric or gas-fired. Its purpose is to corrode at a high rate, in order to protect the rest of the heater from corrosion,

All hot water tanks (save the plastic ones)corrode. It is a given,

The sacrificial anode is usually made of zinc, or a zinc/copper/other alloy. When it gets eaten away from electrolysis (the action of minerals in the water, and the metals components of the hot water tank/heating elements/etc make the entire unit operate as a small battery), it usually turns a nasty, crumbly black.

It will leach into the water, and if enough chunks fall off the anode, it will color the water as you describe.

The SOLUTION, to "FixYa", is to write down the model number of your hot water tank, go to the local Home Improvement store (or Amazon.com) and order a new anode. Replacing it is pretty straight-forward: turn off the water, turn off the heater, drain the tank down a bit from a faucet that is lower than the top of the tank (or the valve at the bottom of the tank) , remove and replace the old anode with the new one (it screws into the top of the tank, and is a large-headed "bolt", maybe an inch-and-a-quarter across).

Now that I have written this tremendous missive, I re-read your question/problem and see I missed the mark.

You have "black water" backing up into your shower.

You've plugged your sewer line a bit. Quit using so much toilet paper, you have a near-stoppage of your line. Pour a bottle of Liquid Plumber (or two) down the shower floor drain, let it sit for a number of hours, and then run hot water down the drain at as fast a rate as you can before it starts backing up to clear the clog.

Your use of the term "black water" makes me think you might be in a RV (Recreational Vehicle) or the like, so your problem may be cold-weather related. A heat-gun or hair-dryer ran along the drain lines (or a big heater aimed under the RV for a while) might unfreeze the clog and allow it to pass into the holding tank or sewer line.

Your "Black Water Tank" may simply need to be emptied, too.

Flush more often (important!), use less paper in each flush, eat less beans, and try to p**p in the RV public restrooms more.

Even so, if your are in an RV, the sacrificial anode in your hot water tank is good for only two years, tops, before it fails and your very expensive hot-water tank starts to leak. Fix it anyway.

Probably bits of rubber from a valve, or di-electric union.
http://waterheatertimer.org/9-ways-to-save-with-water-heater.html#di-electric

http://waterheatertimer.org/images/Bradfor-White-eco-stor-di-electic-500.jpg

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

These black flakes must be in your line or your expansion tank. Remove the filter from your faucet, temporarily, and let just the hot water side run until the water comes out clean. You must flush these black flakes out.

I’m happy to help further over the phone at https://www.6ya.com/expert/jeremy_69f3cc28d95bf514

Water pressure is blowing everyting loose with new heater,give your system a good flush,it will work it self out. RichieRich

You have water heater with two elements.
Two-element water heaters are 240Volts.

1) Lets talk about what makes a 240Volt circuit
See basic water heater circuit:
http://waterheatertimer.org/B220C.html

Open link, and illustration at top of page is your water heater circuit

Notice that two insulated wires come from the circuit breaker and go to the water heater.
These two wires are 120volt each. When these two 120Volt wires combine, they create 240Volts
These are called hot wires because they come from the hot busbars.
There is also a bare copper wire that comes from neutral busbar.
The bare copper wire is a safeguard, and is not necessary for the 240V circuit to work.

Inside each circuit breaker box is 1 neutral busbar, and 2 hot busbars.
Open image below, and it shows typical residential breaker box
http://waterheatertimer.org/images/Inside-Main-Breaker-Box-420.jpg

In a residential home, each circuit takes two wires to complete the circuit.
For 120Volt circuit, you need 1 neutral wire and 1 hot wire to complete the circuit. These are usually a black and white wire. The bare copper wire is a safeguard.
For 240Volt circuit, you need 2 hot wires to complete the circuit, and each hot wire comes off a different busbar. These can be a black and white wire, and sometimes a black and red wire. The bare copper wire is a safeguard.

With a 240Volt water heater the two hot wires connect to the black and red wires located on top of water heater.

2) Let's talk about wiring inside a water heater.
http://waterheatertimer.org/images/WH-w-combined-530.jpg

Open image on link above, and it shows your 240volt water heater wiring.
The 2 hot wires from breaker box connect to the red and black wires on top of heater.
Inside each water heater, the wires are color-coded and will appear the same, or nearly the same, as shown on link above.
As long as your wiring appears like the image, and the hot wires from breaker box connect correctly, and the circuit breaker is working fine, then your water heater will work.

Add a comment any time.

3) More electric water heater links about water heaters, thermostats and tank wiring:
http://waterheatertimer.org/How-electric-water-heater-works.html
http://waterheatertimer.org/How-water-heater-thermostat-works.html
http://waterheatertimer.org/How-to-wire-water-heater-thermostats.html

Hi,
Turn the water off and replace the relief valve...
If there is that much water running out of it the hot water hweater cannot keep up...
Replace the relief valve and then you will have hot water..

heatman101

Your 220v hot water heater does not need the neutral(white) wire coming in. Bare wire goes to ground -green headed screw. Black goes to black, Red goes to red. White gets teminated with a wirenut or some electrical tape.

Hot Water Hot to Cold And back. I had that problem for 2 years. I had a very large shower head from the time I installed the tank-less hot water heater and the water temp would change from one extreme to another. Over time my shower head had stopped working as well as it did so I bought a smaller shower head and installed it and amazingly my water temperature quit changing temperature. I now turn my water to what temp I want and it stays there. It's been working correctly for 6 months now ... until yesterday and it quit working completely which is the reason I'm on here. lol

This is not an uncommon problem. You may notice this problem particularly if you haven't used hot water for a period of time. The hot water heater is probably working, but there is quite a bit of water that has to clear out of the lines before the hot from the heater reaches your appliance. I suspect that the water heater is doing its job, and that is the assumption I am going off of for my next statement. A recirculation system will work well to eliminate your problem. Again, assuming that the hot water heater is in proper working order. I would do my research on recirculation systems before buying one. Often times you get get a relatively inexpensive unit that will do the job for you.

It is probable a lime build up in the bottom of the water heater tank. You can remove the bottom heating element and clean the lime out, keep in mind this sometimes turns into quite a job though. And you may damage the heating element during removal and have to purchase a new element.