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hot water side smells all of a sudden - Answered

On a well with a Hydrogen Peroxide and water softener system.  Warm water side smells sulfury or nasty all of a sudden.  Plenty of salt in softener and plenty of Hydrogen Peroxide being pumped into system.  Due to softener, the watre heaters never had their anode rods installed - so not coming from there.   What is causing the recent smella nd how to remove? 



6 years ago

Turn off the water heater.

Shut off the water supply to the heater.

Open the drain valve and drain the tank completely.

Close the drain valve and disconnect the water supply line to the heater.

Add 1 gallon of white vinegar through the water supply fitting.

Add fresh water to the vinegar and let stand for two or three hours.

Drain the tank and flush with fresh water until the water no longer smells of vinegar.

Close the drain.

Reconnect the water supply line.

Fill the tank with water.

Turn the water heater back on.

I tried doing something like that at first. But after a short time the problem came back. Its a reaction with the elements and other parts of the water heater tank and the water. Cold water will develop a smell also but it takes a lot longer to notice it as the heat in the hot water tank accelerates the reactions. I also use a water softener and for salt I use the super pelins with rust remover to keep the resin bed from clogging up with rust. The water as it comes out of the ground is clear. After a few hours it turns foggy and then after a day a rust precipitate settles to the bottom. If you put the treated water (its been through the softener and filters) in a bottle with something like silverware (stainless steel) and cap it and leave it for a few days or a week it will start to smell like rotten eggs and sometimes even gets a black precipitate forming. It also will change with the water use, as more water is moved through the ground it picks up less minerals. If it sits longer from low usage then it causes bigger problems. Anyway, after trying a lot of things I went with the bleach solution. Its cheap, fast, effective, and can be repeated as often as necessary. Also it is not unusual to use bleach in wells. I know of some professionals who treat the well after they have pulled and serviced the pump and lines and pipes. These wells are sealed from contamination so no bacteria can get in them. After you drag the pump and lines around in the dirt you need to have a way of disinfecting them when you put them back down in the well. So they will pour a gallon of bleach into it and then seal it. After a day of sitting they run the pump and drain the water off until the bleach smell disappears. Then its free of contamination. I added bleach every few weeks to the water heater for years. Then it slowly stopped needing it. Now I never put it in. But the problem sometimes comes back. If I have been away for a few days and the water has not been run when you turn on the hot water it will sometimes spit out nasty smelling black colored water. I just let it run a little bit and it clears up.


6 years ago

If you inject a cup of bleach into the water heater it will kill the smell for a week or so. I have no idea what the hydrogen peroxide is being added for.

A long time ago, I made a thing for doing this. You add a shut off valve and a T to the cold inlet line above the heater. Then make your own "funnel" with adapters to larger size pipes and leave the end open so you can pour the bleach in. SO the way it works is you turn off the cold water inlet (with a valve), open the drain valve at the bottom of the heater preferable with a short hose to a drain. This de pressurizes the heater. Then poor the bleach in the "funnel" and open that valve with the drain valve still open. This breaks the vacuum and the water going out the drain sucks the bleach into the heater. Close that valve after it is empty, shut the drain valve at the bottom and open the inlet valve again. It takes less than 2 minutes total and the bleach disinfects the water and kills the smell. Just make sure you never drink from the hot water side, especially just after you have treated it. You will get a slight bleach smell for a day or 2 but it is way better than that nasty rotten egg smell.

The smell is more than likely coming from your hot water tank (since there's no smell on the cold side). The smell from the tank will have a rotten egg (i.e. sulfur) smell, and will need to be sanitized (and the anode rods inspected). This problem is more prevalent in well water, because municipal water is mostly treated with chlorine which helps to keep odor causing bacteria low.

Here's a good link which explains the cause and how to deal with it.