Hot Water tank odors
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SteveK
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Why not shock it with bleach?
That's a common problem with some water heaters.
Do a search on water heater smell and you should lots of discussion. I forget the details (tank material, anodes, etc) so hesitant to elaborate but you will find it easily. The fix is another story. A friend ended up replacing WH to eliminate the smell.
Do a search on water heater smell and you should lots of discussion. I forget the details (tank material, anodes, etc) so hesitant to elaborate but you will find it easily. The fix is another story. A friend ended up replacing WH to eliminate the smell.
Comodave
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Agree.
C lectric
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One the odour is gone get yourself a pair of water filters to be used between the tanks and the shore supply.
I hae done this for now about 20 years and still have no odour form the water tanks.
Our city water supply is quite clean but is not foolproof. Especially considering we do travel to areas where that cannot be said OR guaranteed.
First one is a standard household filter or about 5 micron. The second one is ceramic 5 micron element available from the local hardware store or from the internet , Amazon.
The ceramic unit will need to be sanded to clean it from time to time. Our ceramic supplier was who suggested the sanding, light sanding.
And YES, I would often smell and taste test the water for any hint of odours.
We sold our boat last fall, early season, and there is still virtually no odour or taste.
This way the junk never gets into the tank.
I learned from my trailering days into California, Washington, Oregon, etc. as the trailer groups could have water troubles also but some never did so I asked a few questions.
I hae done this for now about 20 years and still have no odour form the water tanks.
Our city water supply is quite clean but is not foolproof. Especially considering we do travel to areas where that cannot be said OR guaranteed.
First one is a standard household filter or about 5 micron. The second one is ceramic 5 micron element available from the local hardware store or from the internet , Amazon.
The ceramic unit will need to be sanded to clean it from time to time. Our ceramic supplier was who suggested the sanding, light sanding.
And YES, I would often smell and taste test the water for any hint of odours.
We sold our boat last fall, early season, and there is still virtually no odour or taste.
This way the junk never gets into the tank.
I learned from my trailering days into California, Washington, Oregon, etc. as the trailer groups could have water troubles also but some never did so I asked a few questions.
BDofMSP
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If it's a sulfur like smell I solved mine by simply changing the anode. Hasn't come back in 4 years. I suspect it's because I don't put antifreeze in there anymore, I just bypass it and drain it. But I don't know that for sure.
CharlieO.
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I agree, good chance it is the anode. I started to have the same issue. I only have a basic 120v water heater, so I am just going to replace the whole unit. It looks a bit crusty and that will give me the opportunity to relocate it a bit and add the bypass for winterizing.
If it's ONLY the HOT water that smells like rotten eggs, it may be the sulphur content in the water...or a failed anode in the tank. Here's a bit of "water heaters 101" from Vic Willman,the now retired tech services manager at Raritan:
Anodes are included in the water heater of glass-lined steel tanks to protect the inside of the tank against corrosion from acids in the water, stray electrical currents, etc. Glass lined tanks, when the water heater is being built, are heated up red hot. Then glass powder is sprayed inside the tank and it adheres upon contact. However, it doesn't cover every single crack and crevice inside the tank - it should, but in actual practice, it doesn't. The purpose of the anode is to protect those spots inside the tank that have not been glass-covered from rusting away prematurely. The anode is eaten away, rather than the tank being eaten away. Kind of a backup to the glass lining.
Cheaper water heater tanks aren't glass lined, so an anode will protect the steel walls of these tanks. They'll require replacement a bit more often than the anodes in glass lined tanks. You'll know it's time when the hot water starts smelling like rotten eggs.
--Peggie
Anodes are included in the water heater of glass-lined steel tanks to protect the inside of the tank against corrosion from acids in the water, stray electrical currents, etc. Glass lined tanks, when the water heater is being built, are heated up red hot. Then glass powder is sprayed inside the tank and it adheres upon contact. However, it doesn't cover every single crack and crevice inside the tank - it should, but in actual practice, it doesn't. The purpose of the anode is to protect those spots inside the tank that have not been glass-covered from rusting away prematurely. The anode is eaten away, rather than the tank being eaten away. Kind of a backup to the glass lining.
Cheaper water heater tanks aren't glass lined, so an anode will protect the steel walls of these tanks. They'll require replacement a bit more often than the anodes in glass lined tanks. You'll know it's time when the hot water starts smelling like rotten eggs.
--Peggie
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Thanks all. So, long story short, I don't need a biocide--it's not something growing in the tank?
It is the orignial tank, '86 Sundowner--a square metal tank, guessing mayb 15 gal or less ; I thought about replacing with a typical, small (15 gal I guess) domestic unit, but the fittings, elec. connection (if there is an anode I guess it would be under that plate) etc. hard to get to, and the small drain-out plug in a tight space so draining seems a bed idea since no way to capture water or port the water out. Also not cut off valves I think from supply side--wil have to double check that (prob. with replacing with a domestic unit could be adapting fittings?). I'm thinking it is likely not glass-lined? RE shocking--not sure how I'd get the bleach in there uless I disconnect the hot line and pour in through there. How much Chlorox would be needed? or should I add it to the fresh water tanks and let it circulate that way (there are actually two fresh water tanks, one metal aft and a plastic one under V berth). We actually don't use the on-board water for drinking (or at least have not thus far)--just washing dishes.
It is the orignial tank, '86 Sundowner--a square metal tank, guessing mayb 15 gal or less ; I thought about replacing with a typical, small (15 gal I guess) domestic unit, but the fittings, elec. connection (if there is an anode I guess it would be under that plate) etc. hard to get to, and the small drain-out plug in a tight space so draining seems a bed idea since no way to capture water or port the water out. Also not cut off valves I think from supply side--wil have to double check that (prob. with replacing with a domestic unit could be adapting fittings?). I'm thinking it is likely not glass-lined? RE shocking--not sure how I'd get the bleach in there uless I disconnect the hot line and pour in through there. How much Chlorox would be needed? or should I add it to the fresh water tanks and let it circulate that way (there are actually two fresh water tanks, one metal aft and a plastic one under V berth). We actually don't use the on-board water for drinking (or at least have not thus far)--just washing dishes.
Lepke
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You should drain your hot water tank occasionally to remove sediment that can react with the tank material. All water sources contain some sediment. Some cities use sand filters, some fine particles make it thru the system. Also zinc and rust can flake off city plumbing lines unless you're somewhere that uses bored out logs, and they drop stuff, too. Unless you're on city water, that usually has chlorine in it, you probably have some bacteria in your fresh water tanks. All my water is from RO and goes thru a sanitation UV light before the tanks, yet I still will get bacteria in the tanks. I assume thru the vents. I have bleached the vents by forcing chlorinated water thru them, yet it doesn't stop the eventual contamination. I live aboard so there's a constant draining and refilling. There is no water at my private dock.
About once a year I put a strong chlorine batch in full tanks, so it contacts the top, run some into and thru all the plumbing and let is sit overnight. Then I drain the tanks and make more RO water and flush the plumbing. Then I'm good.
If the chlorine mix is too strong it may effect rubber seals.
About once a year I put a strong chlorine batch in full tanks, so it contacts the top, run some into and thru all the plumbing and let is sit overnight. Then I drain the tanks and make more RO water and flush the plumbing. Then I'm good.
If the chlorine mix is too strong it may effect rubber seals.
Lepke
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I have 4 100 gallon tanks and put about a cup of dairy chlorine that is about 12% into each tank. That's strong enough to taste. I add the chlorine and then add more RO water to make sure the tank is full and touches the tops. After a couple hours of sitting, I run enough through all my plumbing and let it sit overnight. While the plumbing sits I drain the tanks.
I had a dairy. I use that chlorine for laundry because I use about 1/4th as much and don't have to store many jugs for a trip.
I had a dairy. I use that chlorine for laundry because I use about 1/4th as much and don't have to store many jugs for a trip.
So one cup of a12% chloring solution? So add that to the fresh tank (less than a cup if a smaller tank), then run the hot water til it begins running cold, then let it sit over night? If I don't use the water for drinking purposes, can the chlorine remain in tanks, gradually dissipating with use of course, without damaging tanks/fittings while helping keep them clean?
Capt. Stew
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I’d put my money on the anode. Had the same issue when I purchased the boat 6 yrs ago. Replaced anode and it went away. Don’t know about the square tanks but anode should be on the front right around where you can adjust water temperature.
liquidsands
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Just went thru that same problem. Hydrogen sulfide deposits oin the HWH. I changed the anode to a magnesium anode and the smell disappeared within a month. The sulphur content even though small in fresh water tends to drop out in the tank but can't go anywhere so it decays into hydrogen sulphide (rotten egg smell). You could drain the tank and flush if there is a provision for that but it will be neutralized by the magnesium in the anode in a short while and the smell as well as residue will be gone. The zinc in a standard anode catalyzes with the sulphur to make the problem. I found no difference in the stray current tests afterward. The anodes are only 10-15% higher priced. Found mine on Amazon for around $25.
Regarding your filtration: A Filter system between tanks and point-of-use may be useful due to possible creepy things already in the tanks, including corrosion. Also, crypto and giardia bacteria will still exist at less than 5 micron. May I suggest using a throwaway, final pleated filter of 1.0 or .35 micron? Flow rate will still be good and needed protection will definitely be there.
