Steam Generator Failure

[olivero]

I am in  Clearwater and I have the 36 CGM as well. Why is it being replaced? Got pictures of the failure? I am very interested as I would hate to see that on my own.

[ares]

Ironic, you’re in “Clearwater” . I did not take pics, but I can tell you every single time it is “above” water line failure. And when I use the Cleveland Dissolve in unit, I make sure it is full to top & circulated as recommended. Probe extensions are constantly rotting off, anode is toast. I literally had this conversation with him today as I was pulling giant chunks of scale mixed with his rotting boiler out of unit. I feel for him as he is also a lifelong friend of mine, Ive tried to convince him to go Combi, but it’s a small account and he doesn’t want to spend that kind of $$, which over the life of this unit, he will inevitably spend. I will get some pics later this week, as boiler makes it’s way here. 

[ryantruck9]

I read about the pounds of scale! 

In my area we have the complete opposite water quality from most. 

Ihave worked in other markets and have  learned some but am no expert on water

Here TDS is often too low for water level sensors…

 

Where do the boilers fail and leak? Chlorine is terrible, especially when boiled off into gaseous state.

 

I guess what I’m getting at is where is the leak? Way above water level, near or at water line or way below the water level?(normal operating)

 

At the very near top perhaps chlorine gasses attacking the metal. 

At or Below where 5lbs of scale are insulating the bottom plate and heat exchangers tubes(is it a 250 or 300BTU?)

 

I also can’t help but think even with dissolve who(as an end user)has the time to properly flush the unit after especially that often 

 

There is also the annode for galvanic corrosion. 

We need a weaker metal then boiler plate steel to attack with all these dissimilar metals.

 

Honestly if a failed boiler was tested/inspected I’m sure someone could tell you exactly what has happened.

Where it leaks and how it penetrated can often tell the tail.

[ares]

Failure is always above water line, I literally reach in and up and pull mounds of scale off top inside of boiler. Last one at this location looked like swiss cheese around heat transfer tube welds. We do not drink the tap water in this town as it smells like a swimming pool. 

[ryantruck9]

I’m thinking you have a few problems…

It’s mounds of scale above the water line?

Not handfuls of rust or large rust”flakes”

Does the scale go all the way to boiler top?

 

I have heard the charcoal filter does a great job for chlorine.

Will not help with calcium or scale or silt

 

Swiss cheese tubes sound kinda like annode.

We can’t just hang it off a support, need to sand clean the support and hose clamp the annodes “rat tail” to it then ohm it out .

Bottom of annode to plate steel should be a dead short 0 ohm

 

That said if bottom 1/2 of boiler and tubes are thick in scale means they are insulated so they are glowing on call for pressure if their only energy/heat release happens just above water line how long could the tubes live through that.

 

Do you get that purple ish layer in the thick hard layer around the tubes?

[olivero]

Interesting, stainless rusting out has got to be an electrolysis/anode problem. I could see the steel having a hard time under chlorine but you can filter all that out with some carbon blocks.

 

Here is what my boiler looked like after the first 2 years.

[fixbear]

Nice pic’s olivero.  Interesting to see all the pitting from electrolysis.  I’m very surprised that they didn’t make a more positive electrical connection for the anode.  It almost looks like cavitation electrolysis corrosion.  Does the burner have any vibration?

 

 

Ryantruck9:  Where do the boilers fail and leak? Chlorine is terrible, especially when boiled off into gaseous state.

Chlorine does effect the molecular structure of stainless,  but the levels necessary would be dangerous to people as well.  In the gaseous state it is extremely  poison.  Remember, you can not smell chlorine.  Only Chlorides that come from the chlorine doing it’s job. If you can smell it the system has some form of organic material in it that is changing the chlorine to chloramides and needs to be shocked with chlorine. Just the opposite of what most believe.  You can easily get a La Motte test kit for chlorine.

[olivero]

fixbear wrote:

 

Chlorine does effect the molecular structure of stainless,  but the levels necessary would be dangerous to people as well.  In the gaseous state it is extremely  poison.  Remember, you can not smell chlorine.  Only Chlorides that come from the chlorine doing it’s job. If you can smell it the system has some form of organic material in it that is changing the chlorine to chloramides and needs to be shocked with chlorine. Just the opposite of what most believe.  You can easily get a La Motte test kit for chlorine.

Article: Selection of stainless steels for handling chlorine (Cl2) and chlorine dioxide (ClO2) 

 

It also depends on what grade the stainless is, if they chose 308 or 316, that would make a bit of difference.

 

Like I mentioned in the other post, I would add more carbon filters and see if they help, it should.

[fixbear]

Can’t argue with that.  If your on a chlorine, fluorine, or any system with taste or smell problems Japanese charcoal block filters are the answer. They work a lot better than bagged  or pressed charcoal and have a more consistent filtration.

[badbozo2315]

>Interesting, stainless rusting out has got to be an electrolysis/anode problem.

 

>Chlorine does effect the molecular structure of stainless

 

Just to be clear, I believe the photos above are of a Cleveland nickel-plated boiler shell, not stainless. That option was/is several thousands of dollars more than the base steel shell, and will last much longer, according to Cleveland. My info about this comes from about 20 years ago, though, so things might be different these days.

 

We just don’t see many boiler-base units down here in the High Plains of the southeast us low country.