How do I test my water heater for leaks?

[Montenido]

Hi all,
I just returned from an 1100 mile trip from La Paz, MX to Channel Islands, CA. Somewhere on the trip I started having a fresh water leak, with the pump cycling every 5 minutes or so. It got bad enough that if I left the water system pressurized all the water would drain from my tank.

Now that I am safely tied up in my marina I am trying to trace the leak. I have old polybutylene water tubing throughout my boat that is slowly failing. I fix it as needed with Pex and compression fittings. I found a pretty good leak at the cold water inlet of my water heater which I will fix this weekend. However, I also could hear water cascading into my forward bilge from somewhere around my water heater. I can't visually find the source of the second leak, but it is substantial. Is there some way that I can pressure test my water heater? It might need replacing, but I would hate to replace it and still have the big water leak.

Any and all suggestions are welcome. Thank you all in advance, as I know there are some smart folks in this group. BTW, I have a 1991 Californian CPMY 52.

Cheers, Bill

 

[Russell Clifton]

I would think you just turn on the fresh water pump which in turn pressurizes the entire system including the hot water tank.

In the past I thought I had a hot water tank leaking and it just turned out to be a connection on the line going into the tank. It leaked down the side of the tank and came out under the tank on the opposite side.

 

[High Wire]

Check the water heater relief valve for drips. Sometimes the manufacturer runs the tailpipe under the decking and hard to see. Since you are losing water inventory, it cant be the pump discharge check valves.

 

[Comodave]

I bought a selfie stick just so I could put my phone on it an video areas that I could not see. Maybe use the phone to look around places you can’t get to.

 

[Montenido]

Well, I went to the boat today for some troubleshooting and found something surprising. When I left 2 days ago the fresh water tank was full and the FW system was shut off. Today I found my tank empty and my forward bilge full of fresh water. Could there be a faulty siphon break in the system? With the pump shut off water should not keep flowing. Tomorrow I am going to bypass the water heater connections and see if I still can hear water running.

Another interesting find was that the water heater is hooked up to my generator cooling system. That makes no sense because anytime I run my genny, I switch on the electrical for the water heater just to place more load on the genny. See,ms like it would be better served plumbed into one of my mains. Does anybody have a Caat 3208 T/AC motor plumbed to their water heater? I'd like to know where to install the hose connections.

Cheers, Bill

 

[Russell Clifton]

There would be no extra load on the generator. It's just hot water running thru it, not electricity. The hot water would help heat the water in the tank. I have never heard of one connected to a generator, they are usually hooked to a hydronic heating system. But I guess if in the past the boat spent a lot of time at anchor with the generator running it would work.

I have used a stethoscope in the past to listen for water running thru the system. My pump kept cycling but could not find a leak. Turned out a check valve was letting water pass thru. Could only find it because I could hear water running thru it.

Is your hot water heater lower than your water tank? I would think your water tank would be lower. So with the pump off, the water would need to run up-hill to leak out of the hot water tank.

 

[Montenido]

Thanks for the answers so far. Russell, I was able to isolate the leak to the hot water circuit. I disconnected and plugged the cold water into the WH and everything works fine - it holds pressure and does not leak.


After i install my six new house batteries tomorrow I will delve into it further. I like the stethoscope idea. I'll keep you posted.


Thanks and cheers, Bill