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black sediment in fresh water tank
Emptied tanks and winterized, then stored motorhome in Florida.  Went back home for 2 months.  Just back, refilled tanks.  When pumping cold water, bursts of black sediment  coincide with each pump noise.  Hot water is fine.  Additional spicket for filtered water at sink is fine.  Bleach did not solve the problem.  We've pumped out 1/3 of the tank and refilled and the amount does seem to change.  Dumped tank completely. Filled at two different sources - both state parks - Oscar Sherer and Lake Manatee.  The sediment is very consistent and fine and remains suspended.  It is somewhat gritty and stains the sink, requiring a wipe to remove the black.  Magnesium?  We're stymied.  Not sure if something is dissolving.  Not sure where there might be a filter we can't find.  We use a filter at the hose - put on in October. 

Doug and Judy Gremmel
2005 MB
Re: black sediment in fresh water tank
Reply #1 –
Hi Doug and Judy welcome to the Forum.  There could of course be some black sediment in the freshwater tank. Did you just buy this motorhome recently or have you had it for awhile, and this problem just cropped up?     First dump all of the water in the tank. You can't really pump it all out with the water pump. That is why there is a dump valve located inside the outside compartment just aft of the drivers door. That is where the valve is; the water will exit below that compartment onto the ground. Refill the tank partially and dump it again, to flush the bottom of the tank a few times.  If there is dirty water in the tank, it has probably already plugged up your drinking water filter at the sink.
    If I remember correctly (I don't own a MidBath), you can see the water tank, underneath the counter between the stovetop and the sink. Shine a strong light at the tank to see if there is anything obvious.   If there is a fine silt at the bottom of the tank, it could be getting into the water pump and grinding up the rubber flapper valves in the pump. There should be a small sediment filter at the intake to the water pump, meant to protect the pump. They are located behind your power center at the left of the sink area.
    Let us know if you find the problem or have any more symptoms to pin down this problem.  RonB 
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: black sediment in fresh water tank
Reply #2 –
That's a new one.
Sounds as if you may had loaded a large load of bad water. The sediment may be so small that it is passing through the pump's pre-filter.
I wonder if something is coming apart that would produce black sediment.  There is a chance that the water pump's diaphragm is disintegrating, that might explain the black material that does not cleanup well. I can't think of anything else that would do this, most of the plumbing's system is made up of clear and white plastic.
Another possibility is a chemical reaction between two different loads of water, I'm not a chemist, so this is a complete guess.

For the time being, I would continue flushing the fresh water tank and running as much water as possible through the system.
Let us know what you find.

Larry

Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: black sediment in fresh water tank
Reply #3 –
We used the dump value to dump twice and the last of the water both times was clear.  We filled at two separate camp sites.  This could be charcoal from a filter.  We carry an extra pump and will put in on this afternoon.  There is a sediment catcher up above the pump we'll check when we replace the pump, but not thinking that is the culprit.  Too much black.  We've had the coach for several years and use it 5 months out of the year.

Larry - where is the filter you were referring to?  Couldn't find reference to one in the manual,
2005 MB
Re: black sediment in fresh water tank
Reply #4 –
Could it be Manganese? 

It's common for well water in Florida to have high levels.

http://www.floridahealth.gov/environmental-health/drinking-water/_documents/manganese-fs.pdf

It's common where I live too.  Many people install a whole house water filter to catch the worst of it.

I would try to flush and drain the main tank with a city water source (filtered if you can) and see if that improves things.
 
Rich
'03 MB in NC
2003 MB
Re: black sediment in fresh water tank
Reply #5 –

I know that using an under counter water filter is fairly common in RVs. That’s a great idea. However, filtration prior to filling the fresh water tank serves to eliminate a wide assortment of particulates and parasites.

Some of us here on the forum have been using a two stage filter system that uses a 1.0 micron filter before passing the “fresh” water through a 0.5 micron filter. This assures a fresh water tank contains the safest water possible. As safe as 99.9 % can be, anyway. All this for less than $125.00. The standard “Camco Blue” filter is practically useless as its filter allows far too many things to enter your holding tank. Having an under counter filtration system is a bonus for sure.

As far as cleaning your currently tainted fresh water tank, you may want to take additional precautions before using its water. Marine & RV centers sell purification kits to sanitize your entire system.

If you feel the tank has be satisfactorily flushed, you may want to purchase a test kit to check for bacteria and other dangerous parasites. Just a cautionary step. There are threads on the forum that discuss these issues in greater detail. On our last trip to Yellowstone, I tested our fresh water tank using a simple kit I purchased on Amazon. Coliform Bacteria Test Kit for... Amazon.com : Coliform Bacteria Test Kit for Drinking Water - Easy to Use...

If it were me, I would flush the tank as I filled it. Leaving the tanks drain valve opened as I filled it I could monitor the clearness of the drained water. Once it ran clear, I would take the steps I outlined above. It is important, to me, to insure my fresh water tank is filled with clean, safe water since we use the water as intended. Cooking, cleaning and bathing.

Good luck with you project.

Kent


 

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2015 27' RB "MissB.Haven"
Re: black sediment in fresh water tank
Reply #6 –
The water in the tank is clear, as observed coming from the lower outside drain, after filling and dumping twice..  Water coming from the hot water tank and the shower (hot and cold) is clear.  The toilet water is clear. Cold water from the sink in the bathroom seems worse that in the kitchen.

The cold water spurts black with each pump.  When collected in spurts, it is like India ink.  We've pumped out scores of galleons and the concentration  does not seem to decrease.  There are no clumps.  Particles are very small and most stay suspended, but there is some settling, as we observed in a galleon water container.

When not using pump, all water runs clear.
2005 MB
Re: black sediment in fresh water tank
Reply #7 –
I get the feeling that it's common to the pump. Suggest you disconnect the output line on the pump and examine the outflow (if possible).   ::)
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!
Re: black sediment in fresh water tank
Reply #8 –
We're thinking the only source of that much black would be charcoal from a filter.  Maybe the filter for our drinking water spicket, though less than a year old, is defective and backing charcoal back through pipes in some odd way.  We'll stop by Camping World on Sun for a replacement and see if that works.  We'll be on city water and sewer for the next couple of weeks and can really flush everything out.  If we're right and it's charcoal, at least it is not toxic.  But we'll buy our water until we're sure.  Thank God the shower and toilet is functioning and we've got hot water at the sinks.

Thanks all for commenting, and we'll keep checking back for more.

Doug and Judy
2005 MB
Re: black sediment in fresh water tank
Reply #9 –
I think it's a good bet that the 'black sediment' is charcoal from a filter that either wasn't flushed thoroughly before use the first time (and each time after that) or the sediment is possibly due to some sort of defect in the filter itself.

I use an Omnipure K5667 CC inline water filter (www.rvwaterfilterstore.com) and flush the filter before each use; the original instructions recommended flushing the filter for about 10 minutes before the initial use. This is overkill, IMO, but the amount of charcoal that shoots out at the first flush is substantial.
2003 TK has a new home
Re: black sediment in fresh water tank
Reply #10 –
I'm with Joan and the others who say it's charcoal. Whenever I'd hook up a new blue Camco filter, the initial quart or so was nearly black with charcoal. I'd wait until it cleared up, and then I'd stick the hose end into the freshwater filler opening. Still, I used to see some black sediment every time I drained water from the bottom of the tank.

Activated charcoal's not harmful (remember the advice to feed burnt toast to a poisoning victim?) , so I didn't worry about it. Dollars to donuts that's what you're seeing.

(Actually, at today's donut prices, the loser of that bet might come out ahead! ;-)
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: black sediment in fresh water tank
Reply #11 –

If you use THESE  then the first time you use a new one you get a lot of free charcoal.   I ran into that as I routinely flush the hose/filter system before connecting city water or filling the tank.  First time I saw that it was quite disconcerting,  Familiarity breeds content (or something like that)

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Joel & Terry Wiley
2013  31 IB   ORWAN   / 2011 CRV Tow'd LWEROVE
Re: black sediment in fresh water tank
Reply #12 –
Another hose that I would drain is the outside shower, if you have that on your MB. I think that was optional, so you might not have that. And I would also drain the water heater to flush that. Unless that has had a drain valve installed, you'll have to unscrew a plastic plug to empty and flush that.   The filters containing activated carbon, charcoal, do have a lot of powder inside at first use.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: black sediment in fresh water tank
Reply #13 –
Quote from: elsea  - 
Additional spigot for filtered water at sink is fine. 
 
The water in the tank is clear, as observed coming from the lower outside drain, after filling and dumping twice.. 
Water coming from the hot water tank and the shower (hot and cold) is clear. 
The toilet water is clear.
Cold water from the sink in the bathroom seems worse that in the kitchen.

When not using the pump, the all water runs clear.

The two common filters used in LDs are the hose filters and for deck mounted faucets. The bath and kitchen faucets are normally not filtered other than through the pump's inlet filter screen.
Doug and Judy already stated the the deck mounted water faucet was clear and the fresh water tank was clear and had been flushed twice.
They also said that when using the city water supply, there wasn't a problem.
Unless there is another filter, this suggest the problem is in the water pump.

One other possibility is disintegrating faucet washers, caused by the long soak in the local water.

Larry
 





Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
 
Re: black sediment in fresh water tank
Reply #14 –
You mention a drinking water filter.  Is it the ADC-type where the cartridge fills from the cold water of a sink line and has a countertop dispenser faucet?

If so, is the line that feeds it visible?  Can you see the black particulate substance in it?

Have you tried pulling the filter and putting the bypass plug in so there is no filter in the system?

Is it a new cartridge or a previously-used one (if I read correctly, it is not new).  If used, was it left in housing for a few months without use or was it drained and stored elsewhere?

BTW, if it's been in the housing since October, pull it and get a new one.  That's too long for stale water to sit in it.

We have had a previous incident with an ADC filter that is similar to what you are seeing.  It absolutely was charcoal from a filter that failed.  The siphoning effect from the sink water flowing past the fill line to the filter housing was pulling the failed media into the cold water of the faucet.