Hot water tank

[Chona]

We just bought our '88 Carver 3607 and after the hot water tank heats up, the smell is awful like raw onions marinating in sewer. Ran three bottles of odour/sanitizer through it and now fresh water is good and hot water is good as long as its cold. Any ideas?

[Midnightsun]

If its the original it is most likely filled with deposits and oxidation. Best solution would be to replace the tank IMHO, after all, it is 33 years old. Welcome abord.

[g36]

You said you just purchased and I know its mid summer but was this boat recently unwinterized? I've seen in rv forums bad smells coming from some who ran antifreeze through their rigs and it being in the waterheater and not being flushed fully and heating it up and getting a terrible smell for awhile. It may take a bit to go away but eventually it does. I'd probably keep using more frequently for a bit or even just to heat water and run it overboard to turn the water over in it to flush it really really good to get any baked on left overs off. before replacing right away.

[bud37]

I agree about the antifreeze in the hot water tank......that happened to us once with a new boat.....it took a very long time to get the smell out......bleach treatments helped but it really just took time, when you first turn on the hot water is it a bit foamy ? Use the water thru the hot line most of the time, that will help.

Could be a bad anode as well if it has one or just old.

[Rocketman]

You need to sanatize it.
Turn breaker off.
Completely flush till it is nothing but cold water.
Now for the time consuming part.
The formula is 1/4 cup of bleach for 15 gallons of water.
Fill holding tank with bleach and water till full. Then run thru all your hot water faucets until you smell the bleach.
Let sit for 4 hours.
Drain thru the hot water heater your holding tank, fill, drain (do this twice).
Now put 1 box of baking soda into your tank for every 30 gallons of water by mixing in a gallon jug and pouring in to neutralize the bleach. Top off your holding tank, let sit for 15 minutes. Then drain thru your hot water faucet.
Fill with fresh water and drain again.

Now fill and you are good to go.

I do this every year and keeps the boat water tanks like new.

I also drain my water tank when I leave the boat for any period of time. That keeps water from setting and going bad. Refill before I head out.

[Viper]

I agree, the system likely has to be sanitized properly. Personally I like leaving the treatment in the system overnight. Bleach works but you have to be careful as it's pretty harsh and can damage components, especially the pump if you're not careful. I prefer using Camco's Spring Fresh because I don't have to worry about its affects on anything. Run it through the system and leave it in there overnight, then rinse the system thoroughly the next day. Run water through the water tank a couple of times, then you can do the rest using the dockside water hook up instead of your pump. If you want to thoroughly rinse your hot water tank, run a hot water faucet using the dockside hook up.

Fresh water pumps are not designed for continuous duty, they have a duty cycle spec so run it for a while then stop for a while, and so on until it's done. Running it all at once to perform this task will shorten your pump's life.

And I recommend that you remove your faucet screens before you rinse the system.

[Chona]

thanks all I will try those suggestions out. Let you know if i get it fixed up.