Sediment in hot bath water only

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BashDash
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Sediment in hot bath water only

Post by BashDash »

Hi!
I noticed sediment in the bottom of the tub after giving one of my children a bath. Further investigation after child was out and tub was cleaned it was discovered only the hot water does this. My first thought is maybe the hit water heater has an issue. Hot water heater was installed in 2017. Thought it would last roughly ten years. Any thoughts would be appreciated.. thanks!!!
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alpenglow
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Re: Sediment in hot bath water only

Post by alpenglow »

Is it black stuff? If so, perhaps the hot water heater was installed with SharkBite fittings and they are failing.
Marathon Man
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Re: Sediment in hot bath water only

Post by Marathon Man »

A water heater typically lasts 10-15 years depending on the hardness (calcium, limestone & minerals) in your water. They can last longer if you proactively replace the anode rod and regularly flush it.

The way to flush the sediment at the bottom of the water heater: Hook a rubber (not vinyl) hose to the drain valve at the bottom of the water heater and open it up and drain it either outdoors or to a floor drain. Note a vinyl hose will be ruined if you run hot water through it and rubber will be fine. The only caution on doing this is if the drain valve is made of plastic, sometimes the plastic ones never fully shut off properly after flushing. This can be fixed if you put a hose cap (in garden section of big box HW store) on it. If the drain valve is made of brass, it shouldn't be a problem. You'll need to flush this multiple times to try to get some of the sediment out (you won't get it all out). It is important to NOT turn off the cold water inlet valve to the water heater as you want cold water going into the tank at the same time. You'll want to do this flush every 6 months or so, more if you have very hard water. It won't eliminate the sediment, but it should help decrease it.
ClassII
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Re: Sediment in hot bath water only

Post by ClassII »

Purchased a home a couple years back and shortly after moving in I realized the water heater was *40* years old. It was banging while heating and generally sounding like it was going to blow at any moment so one of the first things was having it replaced after we moved in.

To this day we still get sediment in our hot water lines requiring cleaning out the aerators quite often. We did our best to flush the hot water lines out after the new tank was installed but I think there's just too much sediment in there to get rid of it all. Hopefully when it's time to remodel the bathrooms and kitchen we can just bypass most of the old lines with pex pipe or something.
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Thanks for the replies! Is it unusual that the hot water in a sink in a different bathroom has zero sediment? Not sure if this is a coincidence but we think this started happening around same time a plumber fixed bathtub faucet.
random_walker_77
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Re: Sediment in hot bath water only

Post by random_walker_77 »

If you have hard water, this can be a problem. The solubility of minerals in water decreases as you warm the water up. So the minerals in the water tend to precipitate out in your water heater, and it can be really noticeable if you have hard water in your area. Regular flushing as described by JimMolony helps limit the buildup. A water softener can also reduce the buildup.
random_walker_77
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Re: Sediment in hot bath water only

Post by random_walker_77 »

BashDash wrote: Fri May 26, 2023 8:37 pm Thanks for the replies! Is it unusual that the hot water in a sink in a different bathroom has zero sediment? Not sure if this is a coincidence but we think this started happening around same time a plumber fixed bathtub faucet.
Have you checked the sink's filter(s)?
neilpilot
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Re: Sediment in hot bath water only

Post by neilpilot »

BashDash wrote: Fri May 26, 2023 8:37 pm Thanks for the replies! Is it unusual that the hot water in a sink in a different bathroom has zero sediment? Not sure if this is a coincidence but we think this started happening around same time a plumber fixed bathtub faucet.
The high flow rate into the bath stirs up sediment in your tank. The relatively low flow rate into the sink apparently does not cause sufficient turbulence in the tank to disturb that sediment.

So flush the sediment from the tank, as suggested by JimMolony, and see if the bath sediment subsides.
privateer79
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Re: Sediment in hot bath water only

Post by privateer79 »

BashDash wrote: Fri May 26, 2023 8:37 pm Thanks for the replies! Is it unusual that the hot water in a sink in a different bathroom has zero sediment? Not sure if this is a coincidence but we think this started happening around same time a plumber fixed bathtub faucet.


another thing I've seen is that really old valves that may not have moved for a while themselves get corroded/flaky, and the ruber in the valves/cartridges can cause a black or red inky like substance to come out.... its likely that when the plumber repaired your faucet some of this decaying rubber either got in the line, or was left in the faucet and is now leaking out.

anyway... thats my 2 cents :)
Dregob
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Re: Sediment in hot bath water only

Post by Dregob »

BashDash wrote: Fri May 26, 2023 6:31 pm Hi!
I noticed sediment in the bottom of the tub after giving one of my children a bath. Further investigation after child was out and tub was cleaned it was discovered only the hot water does this. My first thought is maybe the hit water heater has an issue. Hot water heater was installed in 2017. Thought it would last roughly ten years. Any thoughts would be appreciated.. thanks!!!
We had that problem. Newer water heaters have a thermal safety expansion tank. The internal rubber bladder had degraded in ours and we noticed black debris but only in the hot water.
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Privateer: interesting thought about the plumber possibly loosening up the debris. Would running the hot water for an extended time help?

Jimmolony: I'm not such a great DIYer but it looks like I can just attach my rubber craftsman hose and direct it outside or to a slop sink and just drain the water heater? Is there anything that can go wrong. I have PTSD from water in the basement....see my thread....

Also... Is this sediment harmful?
Katietsu
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Re: Sediment in hot bath water only

Post by Katietsu »

Can you give a better description of the sentiment? In the most common switch that most here are describing, it is not harmful to people. We lowered our hot water temperature and it made a noticeable difference. Though, if you have a young child, it is probably already. set at the lower end of the acceptable range.
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Seems like dirt....brownish water....at first thought it was from kids after playing outside all day
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Sandtrap
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Re: Sediment in hot bath water only

Post by Sandtrap »

BashDash wrote: Fri May 26, 2023 6:31 pm Hi!
I noticed sediment in the bottom of the tub after giving one of my children a bath. Further investigation after child was out and tub was cleaned it was discovered only the hot water does this. My first thought is maybe the hit water heater has an issue. Hot water heater was installed in 2017. Thought it would last roughly ten years. Any thoughts would be appreciated.. thanks!!!
To OP:
1
How old is the home?
2
copper pipes all over including main feed lateral?
3
Newer home with Pex tubing (blue is cold/red is hot)?
4
water lines to and from the heater are steel, copper, pex, what?

j :D
Wiki Bogleheads Wiki: Everything You Need to Know
privateer79
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Re: Sediment in hot bath water only

Post by privateer79 »

BashDash wrote: Sat May 27, 2023 6:35 am Privateer: interesting thought about the plumber possibly loosening up the debris. Would running the hot water for an extended time help?
I would think running HW for a while would help.. and, if it doesn't go away, or there is more than a fine bit of "dust" I would look in other directions....

I thought it might be that based on the plumber replacing the valve, and it only coming out of that faucet, and nowhere else in the house... its also possible the plumber loosened some build-up in the pipe (especially if they older pipes), and that's now coming out.

.... also it looks like sandtrap had some good diagnostic questions above ;)
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Thanks privateer and sandtrap!

Sandtrap:
House 1950s.
Copper pipes lateral and copper pipes coming to a from water heater.

Odd coincidence this has been happening since plumber has been over.
Topic Author
BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

I've run the water continuously and it doesn't seem to have helped..... and know I found this video saying draining the tank is a bad idea.

https://youtu.be/rzbFYUabi3o
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Just checking to see if there is any reaction to the video saying not to flush the drain.....I know it is a simple thing to try and see if anything happens but I am not the best DIYer and my rule of thumb is to not make a problem worse.....the post uphill said the valve may leak once you do this which has me a bit nervous....
neilpilot
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Re: Sediment in hot bath water only

Post by neilpilot »

BashDash wrote: Tue May 30, 2023 9:44 am Just checking to see if there is any reaction to the video saying not to flush the drain.....I know it is a simple thing to try and see if anything happens but I am not the best DIYer and my rule of thumb is to not make a problem worse.....the post uphill said the valve may leak once you do this which has me a bit nervous....
In the unlikely event that the valve does leak you can buy a cheap cap that will seal the open end.
sunsetting101
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Re: Sediment in hot bath water only

Post by sunsetting101 »

Remember your chemistry 101 class? It's electrolysis. The heavy metals ions (CA+, MG+) from the water supply (probably surface water that has run over rocks that has leached metals from the rocks) wants to strip an electron from what it comes in contact with. The sacrificial anode (magnesium rod) gives up the electron and corrodes. This is intentional as it's better to control that corrosion locally or the corrosion will occur in your pipes or valves. The integrity of the anode breaks down eventually from the corrossion and you get those sediments. This is pretty much what a ship does also with their sacrificial anode in the salty sea. This also happens when dissimilar metals are in contact. That's why we install dielectric unions/connections so that the metals don't touch but rather a material like plastic/rubber contacting the metals.

If possible, I would start inspecting the connections between the copper piping and any different metal contact and see if the copper starts discoloring. Look under the sink at the copper piping protruding through the wall and all the connections. Do any of the fitting look like corroded? If not, you're fine for now. The corrosion will take years so you have time.

I would agree with the old man about flushing the flecks. It's pointless. But it's useful info though to get a rough gauge of how much corrosion has taken place. But I disagree with him about not replacing the anode because the corrosion will happen throughout your piping and valves if left alone for decades.

You can lookup your county's water report to get a gauge of the water quality. Those numbers may change from winter and summer as some counties may shift from ground water to well water. Also, the ranges they provide may be historical values for that area as well. If someone states their water heater lasted x years, you should follow up with what was their water hardness numbers to get a reference point of hardness exposure.
Katietsu
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Re: Sediment in hot bath water only

Post by Katietsu »

BashDash wrote: Sat May 27, 2023 9:09 am Seems like dirt....brownish water....at first thought it was from kids after playing outside all day
This does not sound like sentiment from hard water, at least as I have experienced it.

When did the plumber replace the bathtub faucet?
ncbill
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Re: Sediment in hot bath water only

Post by ncbill »

OP should have the anode rod pulled & inspected...note it usually takes adding a breaker bar to get it loose.

Then drain the tank & remove the drain valve then use a wet/dry vac to get sediment out of the bottom since as the video notes you can't just rely on the water flowing out of the tank.

Cheaper than buying a new water heater even if you have to purchase a brass drain valve to replace a plastic, original drain valve.

Of course you cut off the gas or electric power to the tank before doing any of the above.
hudson
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Re: Sediment in hot bath water only

Post by hudson »

BashDash wrote: Fri May 26, 2023 6:31 pm Hi!
I noticed sediment in the bottom of the tub after giving one of my children a bath. Further investigation after child was out and tub was cleaned it was discovered only the hot water does this. My first thought is maybe the hit water heater has an issue. Hot water heater was installed in 2017. Thought it would last roughly ten years. Any thoughts would be appreciated.. thanks!!!
I'm not an expert and could not diagnose your issue. If I saw this at my house, I would immediately drain and flush my water heater after checking several YouTube videos. Then I'd let the hot water run until it was clear...if possible. The drain and flush is kind of technical; rookies may want to call a plumber to take care of it.

I've been draining and flushing my water heater for the last 7 years (yearly). I always get some slimy and goofy looking stuff...maybe a half a cup; it's never black. I never have sediment coming out to the faucets...except when a water main breaks.

If draining and flushing the water heater and pipes didn't fix it, I'd call a trusted plumber; I speculate that an experienced plumber could diagnose it easily.
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Op here. Update.

Replaced water heater with my father in law as a project. No more sediment. This was 2 months ago. Last week had drain snaked by a plumber in same bathroom as the tub with sediment. Sediment is back in the tub again. Is this a coincidence or did the snake rustle up sediment somehow. I wouldn’t think it would be related.
Chuckles960
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Re: Sediment in hot bath water only

Post by Chuckles960 »

BashDash wrote: Sun Jul 16, 2023 6:36 pm Op here. Update.

Replaced water heater with my father in law as a project. No more sediment. This was 2 months ago. Last week had drain snaked by a plumber in same bathroom as the tub with sediment. Sediment is back in the tub again. Is this a coincidence or did the snake rustle up sediment somehow. I wouldn’t think it would be related.
The drain takes the water out. The hot water comes in. Water does not go from the drain to the supply unless you have a totally messed-up (and dangerous) system.

I did not notice much information in the old thread on what the "sediment" is. White powder, rust-colored, or black stuff? How large are the grains? Is it coming out of the faucet, or floating up from the drain into the filled bathtub?
Mudpuppy
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Re: Sediment in hot bath water only

Post by Mudpuppy »

BashDash wrote: Sun Jul 16, 2023 6:36 pm Op here. Update.

Replaced water heater with my father in law as a project. No more sediment. This was 2 months ago. Last week had drain snaked by a plumber in same bathroom as the tub with sediment. Sediment is back in the tub again. Is this a coincidence or did the snake rustle up sediment somehow. I wouldn’t think it would be related.
If you put a bucket (or other larger container) under the faucet, is there sediment in the bucket? This will help you isolate whether it's coming from the faucet or backwashing in through the drain.
chemocean
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Re: Sediment in hot bath water only

Post by chemocean »

sunsetting101 wrote: Tue May 30, 2023 4:11 pm Remember your chemistry 101 class? It's electrolysis. The heavy metals ions (CA+, MG+) from the water supply (probably surface water that has run over rocks that has leached metals from the rocks) wants to strip an electron from what it comes in contact with. The sacrificial anode (magnesium rod) gives up the electron and corrodes. This is intentional as it's better to control that corrosion locally or the corrosion will occur in your pipes or valves. The integrity of the anode breaks down eventually from the corrossion and you get those sediments. This is pretty much what a ship does also with their sacrificial anode in the salty sea. This also happens when dissimilar metals are in contact. That's why we install dielectric unions/connections so that the metals don't touch but rather a material like plastic/rubber contacting the metals.

If possible, I would start inspecting the connections between the copper piping and any different metal contact and see if the copper starts discoloring. Look under the sink at the copper piping protruding through the wall and all the connections. Do any of the fitting look like corroded? If not, you're fine for now. The corrosion will take years so you have time.

I would agree with the old man about flushing the flecks. It's pointless. But it's useful info though to get a rough gauge of how much corrosion has taken place. But I disagree with him about not replacing the anode because the corrosion will happen throughout your piping and valves if left alone for decades.

You can lookup your county's water report to get a gauge of the water quality. Those numbers may change from winter and summer as some counties may shift from ground water to well water. Also, the ranges they provide may be historical values for that area as well. If someone states their water heater lasted x years, you should follow up with what was their water hardness numbers to get a reference point of hardness exposure.
Yes, The sacrificial anode (magnesium rod) gives up the electron and corrodes, but this magnesium in the sacrificial anode is in its zero valance state with a high galvanic potential.
Ca+2 and Mg+2 in the supply water are unlikely to participate in electrolysis, since it already has had it electrons "stripped". However, they are likely to precipitate as a carbonate (white precipitate) when the water is heated as the solubility of calcium carbonate decreases with temperature.
Actually, in soft water systems, calcium carbonate is added to drinking water to increase the pH and reduce corrosion.
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BashDash
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Re: Sediment in hot bath water only

Post by BashDash »

Thanks for the replies!

Weird. Just did the bucket thing and got no sediment with or without the bucket? I don’t quite understand. I used cold and hot water? Don’t quite understand.
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Kagord
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Re: Sediment in hot bath water only

Post by Kagord »

This is why I never cook with, or drink from the hot water tap.
chemocean
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Re: Sediment in hot bath water only

Post by chemocean »

BashDash wrote: Mon Jul 17, 2023 6:50 am Thanks for the replies!

Weird. Just did the bucket thing and got no sediment with or without the bucket? I don’t quite understand. I used cold and hot water? Don’t quite understand.
With my old hot water heater, I usually got the black particles once or twice after returning from travel, during which I turned off the house water and turned the hot water heater to pilot. I agree with other post that the particles are probably coming from the bladder in the expansion tank or the rubber gaskets in the connections, if you have these types of connectors.

Depending on what the plumber was doing in the bathroom, the plumber might have need to turn off the house water. Depending on how long the job was, the hot water heater might also have been turned down. If the problem continues, you should have the hot water heater looked at, especially if you have the rubber gasket type of connectors to the hot water heater.
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Re: Sediment in hot bath water only

Post by Mudpuppy »

BashDash wrote: Mon Jul 17, 2023 6:50 am Weird. Just did the bucket thing and got no sediment with or without the bucket? I don’t quite understand. I used cold and hot water? Don’t quite understand.
Another possibility, besides those already given, is perhaps there was work on the water main that coincidentally happened at around the same time that the plumber came out. That can stir up sediment in the main line, but it clears fairly quickly with use by all the households on that line. You're primed to notice sediment issues in this particular bathroom because of the past issues, so you'd be more likely to notice transient issues like this. I'd recommend using the bucket test every time you notice the issue, just to help isolate source water from waste water.
Chuckles960
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Re: Sediment in hot bath water only

Post by Chuckles960 »

BashDash wrote: Mon Jul 17, 2023 6:50 am Thanks for the replies!

Weird. Just did the bucket thing and got no sediment with or without the bucket? I don’t quite understand. I used cold and hot water? Don’t quite understand.
As already stated in two posts above, it means the sediment (which you still have not described---you may think the meaning of "sediment" is obvious but it is not) could be floating up from the drain.
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