Water Heater Leaking???

[AllanS]

Hi, just took a short 3-hour trip along the coast, and while tying up at the dock, noticed my forward bilge was pumping water, not just once, but every 15 minutes or so. Went down in the ER to that bilge, and noticed a 1/2" plastic hose delivering clear HOT water directly into the bilge at a pretty good clip (guessing about 1 quart/10 min).

I checked under the engines, but no sign of raw water there. I checked the hot water hoses that run from the port engine to the hot water heater, but they looked fine, on both sides of a bulkhead between the ER and the compartment where the hot water heater reside. I did the "taste test" and the water coming from that hose was NOT salty, so I am suspecting hot freshwater leak.

I inspected all the hot water fittings I could access, under forward head vanity, under kitchen, etc., but no sign of leakage there. At this point, I suspected the hot water heater, and upon inspection, the cold and hot water fittings were dry, but there was a small drip from the pressure relief valve. I tried to see if that 1/2" gray tube connected to the hot water heater, but I could not trace it. Since the bilge pump was easily keeping up with the leak, and decided to check it in the morning, when I found it was still leaking, but not as fast, and the water was not as hot.

Is this a sign of an internal relief valve in the hot water heater that has gone bad? If so, can these be replaced? Should I set up a by-pass between the cold and hot water connections to confirm this? I'd have to check the make of the heater by going out to the boat, but I believe it is 11 gallon capacity..

 

[bobeast]

It is fairly common for the springs in the pressure relieve valve to corrode and weaken. Not sure what you mean by internal. They unscrew from the outside. Easy fix.

 

[AllanS]

All I see from the side of the heater where the relief valve is located is the flip-up handle. Is there a hose connected to the relief valve that carries the water I’m seeing? That is, how is that water leaving the heater? Would “exercising” the flip handle resolve the issue?

 

[bobeast]

Yeah sometimes just exercising the lever will at least temporarily close up the valve, but does point to an issue that will need to be addressed.

The valve should look something like this;

The outlet may or may not have a discharge hose that would normally be routed either into your bilge, or to a scupper.

 

[AllanS]

Ok, that’s great info. Thanks! I’ll review what I have on my heater. If I have what you are showing, AND I can remove it, what specs should I be looking at to purchase a new one? I suspect RV outlets have these?

 

[bobeast]

Ok, that’s great info. Thanks! I’ll review what I have on my heater. If I have what you are showing, AND I can remove it, what specs should I be looking at to purchase a new one? I suspect RV outlets have these?

That depends on the make and model of your particular water heater. Different sizes / pressure thresholds are available. That metal tag, just under the lever should give you the specs you need. Should be able to take it to any marine or RV store and get it matched up. Either that or ask Dr. Google

 

[mrsrobinson]

Year, make and model of boat, would help...

 

[AllanS]

My year/make model is listed on my profile, if that's what you're asking...

 

[AllanS]

As the original poster, I thought I’d follow up with the solution, in case any other cruiser has this issue. As suggested, I found that my pressure relief valve was bad, it had a plate on the unit that identified it as a Watts 100XL, 150psi and 210 degree, 3/4”. I bought one from Grainger for about $20, and installed it after a very laborious effort to get the old one out (standing and bouncing my weight on a large pipe wrench). All is good again. Thanks to all contributors!

 

[bobeast]

As the original poster, I thought I’d follow up with the solution, in case any other cruiser has this issue. As suggested, I found that my pressure relief valve was bad, it had a plate on the unit that identified it as a Watts 100XL, 150psi and 210 degree, 3/4”. I bought one from Grainger for about $20, and installed it after a very laborious effort to get the old one out (standing and bouncing my weight on a large pipe wrench). All is good again. Thanks to all contributors!

Kudos for posting a followup. Glad it all worked out.