How to Eliminate BAD Smelling Hot Water





Introduction: How to Eliminate BAD Smelling Hot Water

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Most people don't have a problem with their hot water smelling bad. But for those who do it can be horrible. The problem is that the water (very often well water) reacts with the magnesium rod in the water heater and makes the water smell more like something from a septic tank. It can be really bad. I mean really bad. Like open the windows and vent the house bad. I had forgotten just how bad but a recent change has brought it all back.

I replaced my water heater this summer. Very often when someone who lives in the area puts in a new water heater they opt to remove the magnesium rod in them. The rod is there to help preserve and extend the life of the water heater. The idea is that the water will attack and eventually consume the rod and not eat holes in the tank itself. It is referred to as a sacrificial rod because it is meant to be dissolved over time. The problem is however that some water has minerals that react badly with the rod. My alkali water does just that, it reacts with the rod and makes the water smell really bad. In fact it even turns the water black. So when I turn on the hot water out gurgles this stuff that is like something from a volcanic hot spring. Not what you want to wash with. Removing the rod solves the problem, but it also usually voids the warranty on the water heater. And it can cut the life of it also. But there is another solution.

If you add a small amount of bleach to the water heater it makes it all better. It's actually pretty amazing that so little bleach can make such a big difference. We are talking about a cup at the most, added to 30 to 40 gallons of water. The problem is how do you get the bleach into the water heater.

That is what I am going to show you.

Vyger's very own water heater bleach injection system.

Step 1: Gravity and a Little Modification

Because of the way water heaters are made it can be pretty easy to do this modification. Even someone with no experience can do it. A few basic tools and some plumbing parts.

The plan is to make a funnel that attaches to the top hot water outlet with a shut off valve. To get the bleach into the water heater is then a simple process. First you turn off the line coming in so there is no pressure in the heater. Then attach a drain hose to the water heater drain and open the drain valve. Some water will come out but then it will slow and almost stop. The water trying to get out the bottom is creating a vacuum at the top of the water heater. If you open the valve that was installed air rushes in and water then goes out the bottom. Anything you put in the funnel will get sucked down into the water heater. SO you put your bleach in it, open the valve and "slurp", its gone, just where you want it to be. Add some water for a rinse and your done. Close the drain valve, reopen the inlet valve and your finished. The heater is once again pressurized and now the water is mixed with bleach which kills the reaction with the rod and the stinky smell it produces.

This is a completely DIY project since as far as I know there is nothing like this commercially available.

Depending on your plumbing, this is what you need to get to make one.

Cardboard --- The glue drips all over and it will not come off. It melts vinyl and plastic. Use cardboard to work on.

You need paper towels to clean the pipes and fittings. You need a saw to cut the pipe. A hack saw works good. A saw with big teeth will not. You need a file and utility knife to clean up the cut ends. You need a marker to mark the fittings and pipe and a wrench and pliers.

You will need to buy a small can of pipe glue and cleaner. Some Teflon tape for the screw threads. You need to get a good valve, preferably a brass one. And whatever fittings you will need for the configuration that you have. Draw out a picture of what fittings you will need and take it with you to the store. Buy extra fittings and plan on taking back the leftovers. It eliminates emergency trips to get more when something doesn't go together right.

Step 2: Dry Fit Stuff First.

Always do a dry fit of everything. That doesn't mean you need to screw it all together and press the fittings all the way in. Just lay stuff out so you know where it will all go. Then start assembling things. Glue takes time to dry so work in sections. Don't try and glue everything up at the same time.

Always remember to remove the labels and price stickers. If you leave a sticker on and it ends up in a glued joint that joint could fail and leak. Clean fittings, clean pipes, clean applicators means clean joints and clean joints don't leak.

Sometimes it helps to file the edges of some fittings. It gives the overflow glue a place to set up and helps seal the joint.

Wrap threads with Teflon tape to help prevent leaking. Don't use to much, it could cause the fitting to be to tight and even split the other piece.

Step 3: How to Glue a Pipe Joint

One of the first things that happens with these applicator in the caps cans is that the glue dribbles all over the threads of the can so when you put the lid back on it glues it on. Hence the large slip joint pliers. Its just the way it is. Also you get glue on your hands. Don't fret about it. It peels off, sometimes in long strips. Its almost like your peeling your skin off.

When you cut a pipe it will often not be straight and will often have burs on it. A large tooth file flattens it out nicely. A utility knife works good for cleaning up the inside edge. If you leave plastic stuff in the pipe it will often end up in the faucet screens of your sink. So the better you clean them up the less junk in the water line.

File a little around the outside also. It will help it seat in the fitting.

Wipe on some cleaner and then immediately wipe it off with a paper towel. If you do it fast the pipe will not be sticky. If you wait a few seconds it will soften the plastic and it will stick to your paper.

Spread glue on both the pipe and the fitting and while pushing it together twist it a little also. They say about a quarter turn. The glue should form a bead around where it meets the fitting. I usually roll it around with my hand (if its small enough piece of pipe) so the glue doesn't drip but instead flows around in the joint. Once it gets stiff you can put it down to dry and work on another joint. Don't put any pressure on the joint while its drying. You want it to set up and be evenly coated inside.

To cut a specific length I use a sharpie and draw a line all the way around. It helps you keep the cut flat so its not at an angle. Its probably overkill but I hate redoing things so I spend a little more time at the beginning to get it right the first time.

Step 4: Getting Fittings at the Right Angles

When I first started gluing pipes I figured out to mark on them where I wanted them to line up. For a lot of things its not important but if your doing non standard angles then using alignment marks makes a lot of sense. You only have a few seconds before the glue stiffens up when you do a joint so marks make it possible for you to get it right the first time.

Step 5: Connecting It to the Hot Watter Line.

This is not a new idea or invention of mine. I had the same type of thing in place on my old tank. When the guys installed the new one I told them they had to put it back on. Well, they threw it out with the old heater so they make a new one. But it had a few problems. They used so much glue that it ran down inside the valve and glued it shut. The top of the "funnel" was so high up I had trouble reaching it and it was in the wrong place. They didn't leave any pipe between the fittings so I couldn't even remove it and do it right. I had to just leave it and make a new one. At least its not expensive to do.-

So once again, this is how this works :

Close the line in to the tank, the arrow points the way to go for the handle.

Drop the drain line to the drain and open the heater drain. The tank depressurizes and then forms a vacuum at the top. Crack the top valve to let air in and make sure its not going to come out instead of in.

Use the bottle and pour the small amount of bleach into the funnel. Open the top valve and "SLURP" the bleach is on its way. Add some fresh water to rinse, slurp, and you are done with that.

Close the drain, turn the water back on. All done.

The hot water will smell a little like pool water. You can smell the chlorine in it. But it is not enough to bother anything. It's way better than the alternative. How often it needs to be repeated depends on your water usage, your water quality, and your water softener. When my water softener needs to be regenerated it will often trigger the bad smell in the water heater. Usually I treat it when I first smell it getting bad and that is the end of that.

Better to smell like a pool than a sewer any day. Yes, life in the country can sometimes be challenging.

A Few Extra Notes

I didn't mention it when I first wrote this but there are of course other types of pipe. The most common are copper and a relatively new one, PEX. This injection device can be made out of copper instead of PVC. But copper is more expensive and you need some experience working with it in order to solder good joints. Copper and PVC can be used together so if you have copper pipes you can still make this out of PVC and use it with the copper. You will need to solder a copper T in place in your copper line and have a threaded adapter soldered to it so the plastic can screw into it. I found that it is best to have a plastic nipple screw into a metal fitting, just like with my brass valve. If you screw a metal nipple into a plastic fitting the plastic will sometimes split.

It could also be adapted to PEX but the way to do that would be to have it mounted directly to the top of the water heater inlet and use that as support. PEX is flexible and would give no support to this if were just spliced into a PEX line. After it is put in place on the water heater the hot water PEX line could be connected to it.

A few more details about connecting to your existing hot water line :

When you decide where to mount this to the existing line, mark it and then dry fit your injector by holding it to the line where you want to cut it. In other words make sure it will fit before you cut the water line.

When you cut the line it will almost certainly have some water in it. It's annoying to have it run down your arm but there really isn't much way around it. If somebody opens up a faucet while you are cutting the line or after it has been cut you might get a lot of water coming out of it. Tell people not to turn any taps on while you are working on it.

Your Saw can easily get pinched and bind up. As you cut through the pipe it will sag. When it does the part that you have already cut will pinch on the saw blade. Don't get frustrated and yank on the saw harder. Just lift the pipe up and it will free the blade so you can finish the cut.

Once the ends of the pipe are cleaned and ready to glue make alignment marks. You can glue in one side of the T and then the other or you can even try to do them both at the same time. But one important thing is to hold it all together for about 30 seconds after you push the pipes in place. Sometimes the fittings will push back out so you need to keep pressure on the joints. If the injector assembly is putting weight on the joint you might want to hold it in place for a full minute or two to let the glue set.

And one last note : Do NOT pressurize the water line for at least 2 hours. Leave the hot water off long enough to give the glue time to dry. I usually go for half a day before I put pressure to the line but the directions say you can after 2 hours.

If there are some things that you don't understand just ask. You can ask here or even in the questions sections. We will all be glad to help you as much as we can.



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    1 Questions


    With most of the heaters I have seen there is a big hex head bolt somewhere on the top of the heater. It is actually a plug. Often the rod is attached to the plug so the entire things comes out when you unscrew it. Or, the rod is held in a bracket of some kind just below the plug. But most are permanently attached to the plug. You replace the rod and plug together.


    question, and I am surprised that nobody has asked it yet.

    do you cover the top of the funnel with something to prevent materials, objects, dust and debris from getting in to it?

    I suppose it could be a smart thing to do. If there were mice in there or something they could make a mess and it could get pulled into the heater. Even something like aluminum foil would work. I have not up to this time covered it with anything but that could deffinately be an option for the future.

    I wouldn't recommend Aluminum Foil touching Bleach, its very reactive!

    hi my name is joe one question all my pipes are soldered on can i put the bleach threw the pressure valve one i drain the tank

    You may be better off taking the cold water pipe loose after turning the water off . And use a Funnel to pour bleach through cold water inlet. That is what I hade to do. Also if your hot water tank is somewhat new you might want to consider changing the anode rod. I tried adding bleach but the smell came right back once the bleach ran off. Now I'm changing the Anode rod which I got on Amazon that has Aluminum/ Zinc that is suppose to eliminate the smell as well.

    how long after you insert the chlorine, will the water be smell ffree?

    The effect is right away. Usually though I wait a little while to run the hot water to make sure the bleach gets a chance to mix and circulate through the whole tank. Like 10 to 30 minutes. The swampy smell is gone right away but there is a bleach smell that replaces it. This lasts for a little while depending on your water use. If you were to run a dishwasher right away after putting in the bleach then by the time the washer is done a lot of the bleach is gone.

    is it possible to sinply put this valve (or a passthrough) system at the water intake of the heater instead? If not, why wouldn't it work? Thanks!

    Yes, if the inlet is on the top of the tank. In fact it would be better than using the hot. The tank that I have has the inlet on the side of the tank about half the way down. Since you are using gravity to pull the mixture into the tank it needs to be at the top of the tank otherwise you will not get the full pull of gravity. In fact it would even be possible for the water to exit out the tank instead of going into it. So it's not a matter of in or out or hot and cold as much as position on the tank.