Answers to questions about RV Repair and Maintenance from RV expert Dave Solberg, author of the “RV Handbook” and the managing editor of the RV Repair Club. This column appears Monday through Saturday in the RV Travel and RV Daily Tips newsletters. (Sign up for an email reminder for each new issue if you do not already receive one.) Today Dave discusses what might be causing a sulfur smell in water.
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Sulfur smell
Dear Dave,
I am getting sulfur smell intermittently in my shower water and now getting it in the ice from the ice maker in my fridge. Any idea what is causing it and how to cure it??? —Paul
Dear Paul,
There are many things that could produce a foul smell that seems like sulfur, such as the gray water tank, inappropriate vent cap, propane leak, or a leaking cooling unit. However, since you says it’s in the ice cubes, let’s start with the refrigerator cooling unit.
If you have an absorption refrigerator that runs on LP and 120-volt power, there is a solution in the cooling unit that is hydrogen, ammonia, sodium chromate, and water. This solution is heated to create a vapor that travels through the cooling unit tubes through an evaporator coil and condenser coil to pull out heat. Some models developed a crack in the tubing if the refrigerator was operated in a non-level position for extended times as it would cause excess heat in the area the solution would pool at, sometime in excess of 800 degrees! This extreme heat would weaken the metal and could eventually cause a stress crack with the unit bouncing down the road. Both Norcold and Dometic had a recall, so check to make sure your unit is not one that falls into the recall. If so, note that the recall was done.
Check in the outside vent
The next thing I would check is in the outside vent. Pull off the cover and inspect the burner assembly, boiler vessel, and all tubing for signs of leaks such as yellow or white powder. Especially check the smell. You might have to pull the unit out. A telling sign is also an inefficient cooling of the refrigerator. If there is a leak, it would make more sense because the ice would absorb the smell, since it’s right there.
Next, dump your gray water tank or tanks and get some Thetford tank cleaner and 1/4 cup of bleach. The water in your rig is generally hard water from campgrounds. After awhile it can get very skunky, especially sitting in the gray water tank. Flush it out good and repeat.
Your plumbing system has a series of vents that go up to the roof to prevent a vacuum. Make sure your vent cap is in place. You might want to install a cyclone cap, which is like a weather vane and turns with the wind to help vent out.
Tank under a countertop
If you have a tank directly under a countertop, the vent pipe cannot go all the way to the roof. Some manufacturers install what we call a cheater vent, which is a pipe stubbed up under the counter and has a siphon cap on it. These caps can go back and allow the fumes of the tank to escape, which might be escaping and filtering through cabinetry.
And finally, it could be a propane leak. However, your LP leak detector would typically go off. I would suggest getting a tester like this one to verify.
Read more from Dave here.
Dave Solberg worked at Winnebago for 15 years developing the dealer training program, as marketing manager, and conducting shows. As the owner of Passport Media Creations, Dave has developed several RV dealer training programs, the RV Safety Training program for The Recreation Vehicle Safety and Education Foundation, and the accredited RV Driving Safety program being conducted at rallies and shows around the country. Dave is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.
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##1710
Sulfur smell in shower water and ice is very unlikely to be caused by any of the items mentioned in the article. The most likely source in an RV is well water from a campground containing sulfur, allowing sulfur reducing bacteria to produce hydrogen sulfide which is what you smell. If the RV is allowed to sit for a long time with the water heater and plumbing system not being used it is even more likely, The Culligan article referenced below is a much better answer. Disinfecting and flushing the system, particularly the water heater, should solve the problem at least until the next time.
I would guess they picked up some high sulfur content water somewhere. We just had this happen at a state park in Indiana. We topped off our fresh water tank at their potable water station and once we got parked and setup, we started smelling the rotten egg sulfur smell. Did a little googling and found by adding a little bit of bleach it should go away. We did that and by the next day the smell was gone.
First thing I thought of was he was in FL. The first time we went to FL for the winter we would gag at drinking their water even with a multi filter system that included a carbon filter. We just switched to buying our filtered water at Walmart or some other store that will we refill our gallon jugs for $.27 per gallon. Now that we have downsized to a smaller travel trailer I have a Camco in line filter to keep trash out of my system and buy the drinking water. I didn’t even consider a multi hundred dollar filtering system as I don’t think a regular filtration system can remove the sulfur taste of FL water.
Could also be the Anode in the Water Heater if you have a Suburban. Some water will react with the standard Anode material causing the Sulfur Smell. The cure is to replace with a Magnesium Anode If I am remembering correctly. Probably a little harder to find than the standard Anode.
Especially if the smell occurs after water has sat in the tank for a week or so. It also depends on the water source. Here’s a good explanation:
https://www.culligan.com/blog/sulfur-smell-in-water-where-does-it-come-from
We have this problem at home but it was only noticeable when we were traveling.
The sulfur smell could also be due to an unused plumbing connection. We had the sulfur smell once in a while in the water from the bathroom sink tap. We traced the hot and cold water lines and found there was a T-connection, hot and cold, for an optional washing machine in a closet about 6 feet away. Since we didn’t have a washing machine, these lines would collect a little stale water and depending on the water pressure it would find it’s way back into the bathroom sink tap. We installed shut-off valves in the line close to the T-connections and it solved the problem.
Reminds me that I need to flush our outside shower, which we have never used. I flush it out occasionally just to keep that from happening.