Thread: Intermittent Darkened Supply Water

Not an inspection question, but I know of someone whose water supply becomes darkened (grayish-blackish) every 2 weeks or so. If they see this, normally by flushing the toilet, they run the water faucets for a minute or so and it clears out. I am thinking it is because they have a softwater system and after it regenerates, something is getting into the supply every so often to darken the water. Then the water is clear as a bell for another 2 weeks or so. Been going on for 6 months or so. They have filtered water via the fridge, so they are not in danger of taking it in. What do you think?

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Its probaby the water softener malfunction, I had one go bad and it turned the water blood red, you could hear my daughter yell for 2 blocks when she turned the shower on and the water came out blood red. pretty scary .

Barry
How old is the house? Do they have copper or galvanized pipe? Is the gray/blackish water only on the cold water side? Do any of the neighbors have the same problem? Does the house sit vacant part of the year? I assume you are on city water. Does the city water come from wells?

Jeff Euriech
Peoria Arizona

The house was built in 2001, and is an upscale home. It is on city water in the Phoenix Metro area, no wells. It has ABS for waste and vent and copper stubbed pex for supply. It is never vacant. Water used daily. Don't know if neighbors have same problem or not. And it does seem to be primarily on the cold side.

Does this coincide with any treatment schedule by the city?

I wouldn't know city maintenance schedules, and if I did, I would have linked that up immediately. So the answer to your question is I don't know. I imagine if it is city related at all, then everyone else in the neighborhood is having the same problem. I'll have to ask my friend to ask his neighbors. Just thought it was a rare problem, but still think it is softwater related since that is in the supply line.

I have a softener and all it does is remove sediment and iron. Salt water rejuvenates the beads in the tank which pulls the particles out of the water. It sounds like maybe the back flush is not working.
Well it's a thought anyway.

Could it be water from the heating system getting into the water supply? Attended an inspection where the backflow prevention/pressure regulator was malfunctioning, and the water from the heating system would get into the house plumbing.

Also, is there a sprinkler system? If so, is there a backflow prevention device?

Black spots in the water is mostly caused by Black Iron Pipe (Nipples) used in the system. Check water softner, water heater in comming connection and if a bacement exixts check the piping to see if any is in the system. See if the company installing it used Black Iron

Gray look to the water or a Milk look in the water is air if you fill a clear glass with the water when it settles out the water will be clear and if black iron nipples were used in the water system you will see black spots in the glass (straingly at the bottom) some watersoftners have a set up that infultrates air into the system in there cycle that causes the Milk look

also if they are having this problem be on the look out for a rotten egg or sulfur smell in the water the water heater anode will react to this and it will start stinking

If i had to put a guess in there id say the softner regenerates every few weeks when it does it puts air in the water and is connected with Black iron nipples at the softner head thats my guess.....

I have found this several times on new homes. I believe it is a bacterial growth in the lines. I have seen it on well systems and city water. From the latest inspection a few days ago, I water treatment contractor told be that they flush the lines with a hydrogen peroxide. I believe changing the water heater is also a good idea as it is harboring the bacteria. enclosed is a picture of a 2007 home that has never been occupied.

Mike Pearson
S. FLA

Is anyone using water while the water softener is regenerating? Is the softener a single or dual resin tank system? If the softener is a single resin tank system, it will be in bypass during regeneration. If water is used during that time period, the water supplied to fixtures will not be softened. If there are kids in the household, that would be a good place to start. They will get up in the middle of the night (while the softener is in regeneration) and use the toilet. That pulls unsoftened water in to the potable water piping.

The comment regarding red water sounds more like a malfunctioning iron filter that uses potassium permagnate for regeneration. Water softeners actually remove very little iron trough the action in the resin bed, but by filtering out iron of large enough particulate size to be "caught" by the resin bed. Hard water ions, on the other hand, are actually exchanged by the resin beads for "soft" water ions.

My area has some neighborhoods where the water can get pretty ugly looking. Typically, these have some sections of water main that are wood, and / or main to house service pipes are lead.

None of the home I have inspected with the black water have had water softeners. So that take that out of the picture.

Mike Pearson
S. FLA

Are there any other common causes of sulfur smell?

The townhome today had an overwhelming sulfur or rotten egg smell from all water appliances. Gas water heater.

The townhome in question is the model home and is about 12-18 months old. I am guessing only very intermittent water use by potential buyers. The agent uses the next door model as base of operations.

Did not speak with builders agent but buyers are going to ask the builders agent about the smell. Is it just this unit or is it common to the neighborhood, etc.

Bacteria collecting on the anode tube is what is causing the smell. This is common if a water heater is not being regularly used.

Most of the time the smell will go away after use for a few days.

rick

Originally Posted by Rick Hurst

Bacteria collecting on the anode tube is what is causing the smell. This is common if a water heater is not being regularly used.

Most of the time the smell will go away after use for a few days.

rick

This was a gas water heater. I do not believe there is an anode tube.

Gas water heaters still have the anode.

Why do you think a gas water heater does not have a anode rod?

Because if you have gas and you blow a rod out your anode............you are in deep xxxx ..........

Originally Posted by Rick Hurst

Why do you think a gas water heater does not have a anode rod?

I thought the anode rod was a sacracifical part to help with galvanic action caused by the electrical heating elements. Since there is no electrical heating element in a gas water heater, then there would be no need for an anode rod.

Apparently I am mistaken about the purpose of an anode rod.

Corrosion within hot water heaters can be caused by water acidity, electrical conductivity, dissolved oxygen, and temperature. Water can react chemically with metal parts inside of the water heater. Acidic water can actually eat away at the metal. This corrosion process is accelerated with temperature. So as we heat the water for our usage, we actually can hurt the tank!

Anodes - The Staff of Life

Depending upon the source of the water supply, the dissolved mineral content can be high, medium, or low. Also, there will be different minerals present. The heating of water within a hot water heater and the motion of the water cause tiny electrical currents to be generated within the water heater. These electrical currents start to eat away at any exposed metal. That's why water heaters have anode rods as a part of their construction. These anode rods are made of magnesium. The magnesium attracts the electrical current and corrodes more easily than the steel tank. However, if the anode rod completely dissolves, the electricity within the tank will begin to look for some other metal. That's why you need to check your anode rod periodically.

Many people know the difference between hard and soft water. Hard water is water that has a high amount of dissolved minerals. When hard water is heated, some of these minerals can precipitate out of the water and form a scale on the inside of the water heater. This scale can flake off and begin to collect on the bottom of the tank. This lowers the efficiency of the water heater by acting as a barrier to the flow of heat from the burner to the water. This scale can also corrode heating elements on electric hot water heaters in a very short period of time. Friends of mine have had to replace electric heating elements every 3 months because of this problem.

Electrolysis

Since we're talking about electricity, let's finish with electrolysis. Iron is the primary metal used to construct hot water tanks. You can see this iron at the top of the tank where the hot and cold water pipes attach to your heater.

Often rookie plumbers or homeowners simply install a copper male adapter into the female iron tank fittings. This metal to metal contact of two dissimilar metals can lead to corrosion.

These connection points need to be isolated "electrically" from the water pipes. There are several different connectors made for this purpose. I, personally, choose to use di-electric unions. Good Luck!

Water Heater Anode Rods

Thanks for the link. It seems I understood the basic function of the rod, a sacraifical part to protect the tank from galvanic action.