Possible to fix a pinhole leak in indirect water heater?

[ElkRiverFJ]

First, the backstory: probably a year and a half ago I purchased a Crown propane boiler and Crown MegaStor 40 gallon indirect water heater for a great price.

Due to other projects, I've never gotten around to working on the indirect water heater until this summer. First issue was that I found the inside of the tank to be completely filled with hard water scale. It has a rather large oval inspection port on the top so I was able to use my pressure washer (small electric model) on the inside of the tank and all the scale flaked off with not too much effort. This made everything look shiny and new inside.

However, this weekend I hooked it up and under pressure noticed a puddle of water around the base. After draining it and taking the insulation off the bottom I found the culprit was a small pinhole in the actual tank. Aside from the fact that I'm scratching my head about how this could happen, as it is a stainless tank, I am mainly wondering if it can be fixed? I am not a welder so I don't know anything about it, other than being stainless makes it even more of a challenge. Should I fix it, or just scrap it?

 

[cityboy172]

Depending on the tanks actual age, I would run the numbers and see if they would warranty it. That would be my first step.

 

[krinkov]

if they do not warranty the tank can be welded with a mig welder.drain the water first.do not use flux core mig.i know about leaks.been welding on my essex 1000 for 2 years.

 

[heaterman]

Crown's warranty is limited to the original purchaser only.

That's how these manufacturer's get away with "lifetime" warranty offers. They know that the average person live in a house for around 7 years. Just went through this on a Buderus tank that pin holed the indirect coil itself. Boiler kept building pressure even though the boiler feed line was shut off. Had a "what the....." moment there until it dawned on me. I've never seen a leak in the coil before this.

 

[peakbagger]

My brother had an Amtrol boilermate that had a factory defect where the coil went though the base flange. It appeared to be a press fit joint. It was guaranteed to the original owner but in order to get one replaced the serviceman had to pull the unit, verify the failure, get an authorization and they would ship a new unit to be installed at a later date. The warranty didn't cover labor. Alternatively he could buy one off the servicemans truck and get it installed during the same service call. He chose to buy a new one like I expect most would.

I got the old one and cleaned up the joint as well as possible and tried to silver solder it. It still leaked a bit, so I sanded it good and sealed it with JB weld on the inside. I have had it online for 10 plus years since. I would suggest you try the same thing.

 

[ElkRiverFJ]

Pretty much ran into what you all are saying on the warranty. Has to be the original owner and even then has to go through an installation contractor.

I don't think there is any way to get anything on the inside, as it is at the bottom of the tank under the coil. I guess I will call around and see if there are any places around locally that would attempt it. Problem is finding someone that actually can do it and knows what they are doing, not someone that just says "yeah, sure, I can weld anything".

I have a sidearm that I could install on the Electric WH. I guess I better decide which project is easier to finish. Fixing the tank or just installing the sidearm.

 

[Bob Rohr]

Pretty much ran into what you all are saying on the warranty. Has to be the original owner and even then has to go through an installation contractor.

I don't think there is any way to get anything on the inside, as it is at the bottom of the tank under the coil. I guess I will call around and see if there are any places around locally that would attempt it. Problem is finding someone that actually can do it and knows what they are doing, not someone that just says "yeah, sure, I can weld anything".

I have a sidearm that I could install on the Electric WH. I guess I better decide which project is easier to finish. Fixing the tank or just installing the sidearm.

Was it a new tank, or used when you bought it? High chloride levels, found in some city water can pinhole stainless. And put a meter on the piping to make sure you don't have stray current trying to ground through the tank or piping connected to it.

Most welders have the means to weld stainless. It can be stick welded, MIG, TIG, even brazed with a fluxed rod and oxy-actylene torch. Torch might be risky if the insulation is foamed around the rest of the tank?

 

[jebatty]

I used J-B Waterweld to fix a pinhole leak in an expansion tank for the hot water heating system in a rental house. Inexpensive, fast, and no issue after two years.

 

[ElkRiverFJ]

Was it a new tank, or used when you bought it? High chloride levels, found in some city water can pinhole stainless.

It was a used tank. There was a massive amount of what I initially called hard water scale inside the tank.

I used J-B Waterweld to fix a pinhole leak in an expansion tank for the hot water heating system in a rental house. Inexpensive, fast, and no issue after two years.

Huh, that was my first thought..but I didn't think JB weld would be appropriate for something that could see 60PSI and high temps?

 

[jebatty]

I think JB is rated to 300F. On my expansion tank, pressure is about 20 psi and 180F water.