Rotten egg smell for water heater

I stand by my statement that came from the article posted. Check out a google search and you will find articles stating the same thing. Your own article states that it could be a chemical reaction. yes a chemical reaction with the anode.

Wrong?
I stand by my previous post.

The Atwood has an aluminum tank that acts as the anode while the metal and other contaminants act as the cathode.

This is from the Suburban Service Manual: Suburban Service

E. Odor from Hot Water System
Odor from the hot water system is not a service problem, and many water supplies contain sufficient
amounts of sulphur to produce an odor. The odor is similar to rotten eggs and is often referred to as
sulphur water. It is not harmful - only unpleasant to smell. Sulphur water can be caused by a
chemical action or by bacteria. The solution to eliminate is heavy chlorination of the water system.
Add about six ounces of heavy chlorine (common household liquid bleach) to each ten gallons in the
water tank. Then run the heavy chlorinated water through~ut the system, opening each faucet one
at a time until you smell the chlorine. Let the RV sit for a few days and the chlorine should take care
of the problem. Then you'll need to take care of the chlorine. You may consider adding a filtering
system that removes chlorine and prevents sulphur water.


I've had 2 Atwood and 2 Suburban WH's in 4 RV's and all of them at one time or another had the sulfur egg smell. Replaced an anode (still in good shape, manual states to replace if greater than 75% eaten away) in one of the Suburban heaters and took 2 months off from camping, smell was back just as bad. The only time a sacrificial anode rod on a Suburban Heater needs changing is when it has been eaten away to the point it offers no further electrolysis help. Atwood W/H have no rod and can stink the same. It's from non use. Flush it out and use the darn thing and the smell will disappear.

mark5w wrote:
Time for either the anode to be replaced or a good flushing. Some corroding anodes react with certain well water to get that awful smell.

Its an Atwood water heater. Anode rod not required but it had one when we pulled the drain plug which was metal. The rod looked brand new except for the calcium deposits. We sanitized the system twice with a heavy dose of chlorine and seams to have taken care of the smell

Retired JSO wrote:
The smell is from not being used. It has nothing to do with the anode which is there to control electrolysis. Lots of State Parks we frequent have their own water system, most just well water non chlorinated. Although we make it a point to camp every other week, we sometimes have to miss a trip and the extra 2 weeks, we sometimes get the smell. If your friend uses the coach regular, then the smell will go away. In any event, just flush the tank with clean water a few times and the smell will go away.

Sorry, but you are incorrect about the anode rod as this article states:



Atwood (or Atwood Bowen for the real old timers)

And Suburban (formerly Mor-Flo and American Standard).

Many of the questions are specific to one brand only. There are some differences between the two. I will try in this article to address any differences that would be of consequence to the average RV'er in normal use and operation. It is not my intent to get into specific detailed technical troubleshooting and repair, but to address some common complaints and questions that the average RV'er can easily address.

Rotten egg smell in the hot water.

One of the fun things about RV repair is it is very common to find varying opinions about solutions and causes for the same basic problem. I have found three different techniques to this problem. The cause always seems to be pretty much the same however.

Cause: Sufficient amounts of sulfur in the water to produce an odor. This is caused by the electro-galvanic action of either the special 15% thickness of the type 7072 aluminum (pure aluminum and zinc) that is fused to the inside of Atwood tanks since 1988 or the anode rod in the Suburban. Bacteria in either brand can also cause it.

Step 1 : Turnoff the water heater and let water cool if need be.

Step 2 : Drain and flush the tank. By flush I mean let fresh water run through the tank quite awhile and get out all the sediment that can settle in the bottom of the tank. The agitation action of the water coming into the tank should help unsettle and flush the sediment. Compressed air can also agitate the sediment or you can use a bent stiff wire or brush and go in through the drain hole to stir things up. If you do this be careful not to damage the threads. This is also a "tool" available in most RV stores that hooks on the end of a water hose and is specifically designed for this purpose. The primary objective here is to get the sediment out. I might also advise to be certain the water you use to flush does not have a sulfur odor. Keep the drain hole clear as the sediment can stop it up.

Step 3 : (optional): Remember the varying opinions? Here is one. Fill the tank with 2 parts distilled vinegar to 1 part water and let set at least 2 hours. That is a lot of vinegar! I checked to be certain my manual did not have a misprint and that is the correct ratio. Let it sit for a couple of hours and rinse with fresh water. To fill the hot water tank only you must go through the T&P valve (the valve on the top of the outside of the tank with a lever and metal tag on it.) Screw a male fitting into it and let gravity feed the solution in through a funnel and flexible hose (open a hot water faucet to let air escape). You can also go through the drain valve or anode rod opening using the same procedure. You can open the T&P valve to let air escape. Be sure to hold funnel/hose high. The third way is to pump it through the fresh water system. This will also pump the vinegar water into most of the rest of the system. You will need to flush real good before proceeding to the next step.

Step 4 : (optional): Add about 4 teaspoons of household detergent for every 10 gallons of water into the fresh water tank. If you will add a little detergent then water then detergent then water, and so on this will help mix the solution. Run this solution through your whole water system (all faucets, valves, and toilet). Use your water pump and continue putting in water and pump through until the detergent is gone. Be certain to remove faucet aerators and shower heads during this procedure. Clean and reinstall them before the next step.

Step 5 : (recommended option): Do the same as step 3 using common household bleach at 5-6 ounces (2/3 to 3/4 cup) per 10 gallons of water. You might let this set in the system for a couple ours to a few days. Then flush out till chlorine smell is gone. Some people advise this step may need to be repeated several times.

As you can easily see, Step 4 & 5 also help freshen your whole system.

Step 6 : When you are convinced you have all the vinegar, detergent, and bleach out, close the system and refill the water heater and the system.

The smell is from not being used. It has nothing to do with the anode which is there to control electrolysis. Lots of State Parks we frequent have their own water system, most just well water non chlorinated. Although we make it a point to camp every other week, we sometimes have to miss a trip and the extra 2 weeks, we sometimes get the smell. If your friend uses the coach regular, then the smell will go away. In any event, just flush the tank with clean water a few times and the smell will go away.

Time for either the anode to be replaced or a good flushing. Some corroding anodes react with certain well water to get that awful smell.

The following is from the Atwood service manual.

1. Turn off your main water supply. Drain your water
heater tank. Reinstall drain plug. Remove the
pressure-temperature relief valve. With a funnel
use 4 parts white vinegar to two parts water. (In a
6 gallon tank that would be 4 gallons vinegar to 2
gallons water).
2. Cycle the water heater, letting it run under normal
operation 4-5 times. At no time do you remove the
vinegar from the tank Once this has been
completed, remove the drain plug and drain the
water heater.
3. After thoroughly draining the tank, to remove the
sediment, flush the water heater.
If you elect to use air pressure, it may be applied
either through the inlet or outlet on the rear of the
tank or applied through the pressure-temperature
relief valve. Remove the pressure-temperature
relief valve and insert your air pressure through
the pressure-temperature relief valve coupling. In
either case, with the drain valve open, the air
pressure will force the remaining water out of the
unit.
If air pressure is unavailable, your unit can be
flushed with fresh water. Fresh water should be
pumped into the tank either with the onboard
pump or external water pressure. External
pressure may be hosed into the unit either
through the inlet or outlet found on the rear of the
tank or the pressure-temperature relief valve
coupling located on the front of the unit.
Continue this flushing process for approximately
five minutes allowing ample time for the fresh
water to agitate the stagnant water on the
bottom of the tank and forcing the deposits
through the drain opening.
4. Upon completion of the steps above, replace the
drain plug and the pressure-temperature relief
valve.
5. Refill tank with fresh water that contains no
sulphur.

Had that problem in a house for sale -- had left the water heater on (foolishly) for months, with no use. There is a type of bacteria that loves to grow in that environment. Luckily, the solution is easy -- drain and flush, with a little bit of bleach, then lots of fresh water 'til the small is gone.

How about a battery that needs water - that smells pretty bad too.

Not intending to hijack the thread, but has anyone ever used the water purification tablets that were available when I was a scout? I don't know if that would help the smell, but maybe?