New Seaward/Whale S-600 water heater leaking fresh water?

[jonelli]

Hi All, I recently replaced my water heater because it was old and I had a coolant leak which turned out to be the old heater hoses.
Last weekend I noticed my fresh water pump occasionally engaging and found fresh water in the bilge.
After hunting it down, I found a big puddle of fresh water under the new water heater. I checked the fresh water hoses and didn't find anything suspicious, and can't see any indication at the hose barb connections of leaks on the outside of the unit. I'm losing about 4-6 gallons of water now over 24 hours.
Does anyone know if I should suspect the new heater or just start replacing hoses anyway?
Is there a creative way to test it without ripping it out again? I'm really tired of changing coolant.

 

[Davidasailor26]

You could connect the input and output hoses together directly, bypassing the heater. That would help isolate the problem to either the hoses or heater. I guess it wouldn’t eliminate the connections as the problem but in the process of disconnecting and reconnecting the hoses you might fix any connection problems anyway.

 

[kloudie1]

The other thing to check is the PT valve.. it usually has a lever on it to bleed the fresh side .. if that lever is jammed or the valve is bad or has a small peice of debris in it, it will leak.
Amazon.com: Rheem SP12574 Temperature and Pressure Relief Valve,Small : Industrial & Scientific

 

[dlochner]

And it might not be anything associated with the heater install, it could be a near by fitting that is leaking. As vinyl hoses get old they become harder and shrink a bit, this can result in leaks. After awhile even tightening the clamp won't stop the leak.

Did you install a check valve on the inlet? If not that could be the cause. As the water heats up, to as much as 160° when motoring, the increased pressure will push back on the cold water supply and cause leaks at the connection. When the water cools and pressure returns to normal, there is no leak.

 

[jonelli]

The other thing to check is the PT valve.. it usually has a lever on it to bleed the fresh side .. if that lever is jammed or the valve is bad or has a small peice of debris in it, it will leak.
Amazon.com: Rheem SP12574 Temperature and Pressure Relief Valve,Small : Industrial & Scientific

I checked the PT valve. Seems to work as expected. Its pressure release hose goes into a small cup, and it was dry. I can test the lever easily and it works.

 

[jonelli]

You could connect the input and output hoses together directly, bypassing the heater. That would help isolate the problem to either the hoses or heater. I guess it wouldn’t eliminate the connections as the problem but in the process of disconnecting and reconnecting the hoses you might fix any connection problems anyway.

Yah, I could do that just to eliminate the hose question. The connection at the barbs looks good to me. The hoses are pushed all the way on, and the clamps are squeezed very good.

 

[jonelli]

And it might not be anything associated with the heater install, it could be a near by fitting that is leaking. As vinyl hoses get old they become harder and shrink a bit, this can result in leaks. After awhile even tightening the clamp won't stop the leak.

There are no other fittings near the water heater. The hoses go from the heater all the way to my sink/counter, about 6 feet of length before any fittings, and the big puddle is under the water heater.

Did you install a check valve on the inlet? If not that could be the cause. As the water heats up, to as much as 160° when motoring, the increased pressure will push back on the cold water supply and cause leaks at the connection. When the water cools and pressure returns to normal, there is no leak.

Never had one before, and I don't see any leaking at the connections that I see from the outside.

 

[dlochner]

Never had one before, and I don't see any leaking at the connections that I see from the outside.

You might consider adding one as a safety feature. When the water expands it backs up into the freshwater system. When the cold water tap is turned on, the pressure from the HW can force its way out of the tap. It can also heat and expand the vinyl hose to excessively high temps and pressures. Older hoses are exceptionally vulnerable.

 

[jonelli]

>>>>>>>> I think I know what it is! <<<<<<<<
I just called them and they said 99% of the time its the connections at the water heater, but they also reminded me that they SHIP the new water heaters with the intake nipples uninstalled, you have to put them in yourself. Now, jogging my memory, I remember having trouble getting a wrench around the nipple hex part because the metal case is in the way. I don't remember if I put anything on the threads to seal it either, but I'm pretty sure I put teflon tape at least on them.
I'm going to first try to tighten them up somehow.

 

[jonelli]

I guess this will give me opportunity now to install the magnesium anode I bought.

 

[Rick D]

I think you are doing a good job of eliminating most of the common sources. FWIW, I had the same issue with my new Whale HWH about six months ago after installation. I found that the leak disappeared after a week. Something seated. However, I was not leaking anywhere near the volume you are. I would check what you suggest and then, if that does not work, get another and return this one. Good luck.

 

[jonelli]

I had some sikaflex 291 (4200 equivalent I believe) and used a bunch of that as thread sealant. I also spent $18 on a deep socket and adapter that fit on the brass nipple hex patterns so I can properly tighten them.
I pulled out the drain spigot and replaced it with the magnesium anode. I noticed the drain spigot had quite a bit of sealant on it too.
Only had time to spend about 1-2 hours on the boat afterwards to wait and see and didn't notice any leaks yet.

 

[jonelli]

So, it’s still leaking but maybe not as much as before. I put lots of sealant on the fittings before tightening them with a socket wrench. I removed the drain spigot and installed the magnesium anode also with sealant and a socket wrench. Not sure what else I can do now. I’m bummed it’s still leaking. What a pain in the arse.

 

[jssailem]

The Whale manual indicates:

• The requirements for NPT (National Pipe Thread) are spelled out in ANSI B1.20.1
• Creating a leak free NPT connection involves the use of thread sealant tapes

I would confirm that you have undamaged NPT threaded fittings. If suspect replace. Use thread tape sealant. Assure that the hoses and their fittings are not leaking. Pray.

 

[jonelli]

The Whale manual indicates:
View attachment 218039

• The requirements for NPT (National Pipe Thread) are spelled out in ANSI B1.20.1
• Creating a leak free NPT connection involves the use of thread sealant tapes

I would confirm that you have undamaged NPT threaded fittings. If suspect replace. Use thread tape sealant. Assure that the hoses and their fittings are not leaking. Pray.

I used brass ones and a lot of sikaflex 291 sealant. I'm not sure it's really leaking... Last night I spent a few hours and it didn't have any water in the bilge.

 

[jssailem]

That is definitely encouraging.