Hot Water Tank leaks

[woodduck]

The cabin in our 2004 25' C Dory cruiser was accumulating water from an unknown source and it was driving me crazier. I put double clamps on all of the hoses and that did not resolve the problem. I removed the water tank and discovered the insulation was all wet. I filled the water tank with water after I removed it from the boat and no leak appeared, so I reinstalled it and put pressure to the tank via the water pump. Leak (water) appeared again. Removed the box that surrounds the tank and put pressure to the tank after I reinstalled it in the boat. Observed 2 to 4 streams of water coming from the seam on the tank. I found my leaks!!! I contacted Seaward Products about the problem. I was asked if I ever checked the anode in the tank? I asked what anode? To the best of my knowledge Seaward does not normally manufacture the 6 gallon tank with an anode..they put a drain valve in that spot. So, I purchased a new tank from Seaward and an anode which will screw into where the drain valve is located. The cost of the tank is $95.00 and the anode is around $20.00. Anodes do for tanks what zincs do for boats, engines, etc. I want to have a drain, so I'll find a threaded aluminum fitting, drill a hole in the lower part of the tank and install the anode there. Anyone else ever have this problem? Now you know where to start if you have water from an unknown source in your cabin. Good luck.
Ken------Wood Duck

[Sea Wolf]

Ken-

Very interesting! And a nice report!

Maybe you can put a "T" into the existing hole in the tank (middle leg down), install the anode into it so that it projects into the tank somewhat, and put a drain on the bottom part of the "T". Just trying to save you drilling an extra hole in the tank, etc. You may not even have to have the anode projecting into the tank, but I think it would work better that way electrically with the water's conductivity resistance.

Joe.

[localboy]

Oh, boy. One more thing to remember. Thanks for the info. I intently dislike water leaks as locating them is nearly always a PIA.

[thataway]

Interesting, and I am surprised that there would be galvanic action in an aluminum tank which is not subject to pressure, or current much of the time. (I assume that you don't leave the power on the heater). It is possible that there is a "current leak" on the 110 v side.

I have never seen a leak like that in a water heater--and I would be suspect of improper welding rod, current leak or improper weld. It would be interesting to cut into the tank. In fact I would do that before drilling for an annode. How thick is the tank, and can you get a good seal with a tap and pipe thread you will use for the annode? Usually the fittinds are welded into the wall of the tank, and the fittings are considerably thicker than the tank. I have seen leaks in Taiwan and chinese SS tanks, but that is due to poor metalurgy.

[woodduck]

Greetings CBRATS, Thanks for your input & responses. We rarely use our hot water tank to heat water, but it has water in it most of the time. I am told by others including the manufacturer, Seaward products that it is very important to empty the tank when not in use, otherwise corrosion will more readily occur. The representative at Seaward informed me that the weld around the circumference of the tank is most vulnerable to corrosion...it's the longest weld. I am ready to have a new fitting welded into place 2morrow and I'll insert the anode and ready for our trip to Lake Powell & beyond, Leak free. I'll also check the anode frequently...every 3 months or so when we are in the boating season. Those with travel trailers and all other R.V. products with hot water tanks should check the anode in the hot water tank as well & don't leave the tanks full of water as I have learned.
Ken

[Doryman]

How the heck do you empty the hot water heater? We usually keep water in the fresh water tank and AFAIK it goes automagically from there into the hot water tank. We empty and/or add RV antifreeze to the entire water system for winter storage, of course.

Warren

[woodduck]

Hi Warren, In our 25' Cruiser the tank is easily emptied via a discharge valve located on the lower left side of the tank. It is very conspicuous. I don't know where the tank is located on your Cat, so I can't help. I understand it may be difficult to empty the tank in your boat. Sorry, maybe some else will come to your rescue. If you have not had any problems to date, maybe you are okay and just maybe I was the one with the bad luck for everyone else. Take care and see you at Lake Powell. Ken

[Doryman]

[matt_unique]

Yeah our Tomcat's are plumbed with the hot water tank between the source and all other faucet's. We can empty easily, but the moment you hit the Water Pressure switch she will fill up. We would have to use a hose to bypass the system, just as (some) do for winterization.

[localboy]

Mine is the same as Ken's. The hot water tank drain hose goes to the shower drain box that is located undet the rear "closet" and is discharged overboard via the bilge pump.

[thataway]

On my Tom Cat, the drain line, goes up OVER the top of the tank and then to the shower sump... maybe OK for filling with antifreeze, but not possible to drain the tank. You have to unscrew the drain line, and screw another hose bib into it and drain into a shallow pan (6+ gallons). My boat may have been improperly rigged--but since I have never drained it--I haven't worried about the route of the drain--just seems strange.

[localboy]

That just doesn't make any sense. How could the rigger expect water to defy the laws of physics and gravity and travel UP a drain hose, while relying on nothing more than gravity to drain the tank? Sometimes I wonder (pessimistcally I might add) about small details on our boats; like mounting a non-sealed, non-water exposure rated fresh water pump in the wet/humid bilge on the newer 25's. Don't get me wrong, I still love our boat and it is nearly perfect for our needs, but small, stupid, poorly designed/rigged things like this make me wonder about QC in general.

[woodduck]

Greetings, I remember Roger who owns Dreamer describing the C Dorys as "quirky" boats and that they are. We have owned a 22' C Dory cruiser and have enjoyed our 25' cruiser for the past 5 years....I can almost dock it without a big incident. Anyway, we'll enjoy our boat even more now with the new hot water tank and no more leaks. Today, our local expert welder cut a hole on the front of the tank and welded a fitting into place where I intended to screw the anode into...the lower right hand side of the tank. Guess what? Could not put the anode in that place because there is an obstruction inside of the tank...don't know what it is. Anyway, decided to place the drain valve in that location and screwed the anode into the fitting that once housed the drain valve and everything is excellent...the tank even heats water, so I must have rewired everything correctly. All I have to remember now is to check the anode occasionally and properly winterize the boat. Take care and enjoy your boat(s). Thanks for all of the input.
Ken

[forrest]

If you drain your hot water tank be sure and turn off the source of power.
Forrest

[Jack in Alaska]

FYI...........I recently saw anodes for hot water heaters that also had a small drain valve in the nut to drain the tank w/o taking the anode out. I think it was at our local RV parts store.