Well, we got a leaky boiler... LGB 7 - update 10.13.17, 4 pm - wanded..

MilanD

I flooded and soaked the inside of the boiler with lye (caustic soda aka sodium hydroxide), at a few burns getting water to some 140*F per my thermometer. Squeeky clean water after a few hours of soaking and 2 rinses. Nice, and did nothing to descale.

Question now is: to Rydlyme or not...

The sales manager is convincing me the product is safe on any surface with only caviat being under deposit scale (scale that may have filled a hole, which may cause a leak once removed, naturally). That's a biggie...

So, I am convinced that at least one other blister or scale mound in there, which I observed, will cause more failures in the future. When that will be, I would only know once it actually happens. With RO water and all that, it may not for another... who knows how long. If it keeps going w/o failures, I'll pat myself for not seeing anything. But when the leak happens, I'll kick myself for not descaling.

On the other hand, if I descale with Rydlyme, at any time if the leak develops, I'd suspect descaling did it and also kick my self. But, if it keeps going strong, I'll pat myself on the back and say "good thing I did this".

Damned if you do, damned if you don't.

Question, will demineralized water absorb any Ca or Mg from the scale, in essence, do a reverse chem reaction and reduce the scale over time? I think I read somewhere this is happening with some scale structures.... CaSO4, I think, but not CaCO3. Boiler scale should be CaCO3, right?

Koan

I know even having to go down this road must be disappointing. I remember your old boiler lasting much longer. Makes me hesitant to replace my 50 year old horrendously oversized American Standard boiler.

MilanD

Thanks @Koan! Yes, it is...

The same exact boiler, only newer. 6.5 heating seasons... Same exact operations under steam/water loss. The other one lasted until we tore it out - 20+ years. Its sections were actually holding quite well, but the base and burners were gone - plus it was oversized. Same exact op scenario with this one - but ciao bello to the end section after 6.5 heating seasons...

I hope we won't have to bite the bullet on a new one for a few more years after I finish implementing all the water quality solutions. I only wish I knew then what I know now... oh, "steam coming out of a receiver vent - well, that must be normal, it's a steam boiler afterall"... ugh... didn't even occur to me to ask about it until last year, after looking at Dan's "Greening Steam" book, out of curiosity on how to make this boiler perform at its best. Then in was "Oh! Steam coming out is bad!..." Not one of the 2 techs I used mentioned it... ugh... oh well, one lives one learns (hopefully).

What is your thinking on changing your boiler? Is it strictly out of it being oversized? Can't you do anything with controlls like the others here have done? Your system is 2-pipe, right?

Koan

@MilanD - yes it is 2 pipe - I have a slightly dialed down gas valve (with a combustion test) but the boiler is 750EDR for 400 EDR of radiators. It is way oversized. It is also nearly 50 years old!

These are the two compelling reasons to change it, but with new boilers not even making it ten years that call is much harder. I am starting to look at vacuum and cycling - like Pulse Width Modulation firing , cycling, but not at pressure limits of 8 OZ., and hopefully maintaining a vacuum to ; a) allow the water to boil at lower temp. and b) not allow the air to re-enter and have the steam pushing it out of the way.

I am starting to look at this now, but I am a ways off with all the other home projects now.

I think I may try a main vent that seals on vacuum, then maybe add a timer pulsing system, or I may go the solenoid route or even use a vacuum pump on startup. gotta think it through as far as cost benefit.

really sorry to hear about your "young" boiler failing. I am sure that came as a shock.

MilanD

@Koan

My issue was steam loss which I wasn't aware was an issue for the past 6 seasons with the new boiler installed, and the fact that my water is extra hard: 181 mg/L. These 2 factors contributed to creating a few large scale blisters inside the boiler. One pinhole leak developed on the opposite side of that blister... After inspecting the boiler, with that one section off, I discovered only one more larger blister, but smaller than the failed one, and below the waterline vs. above the one that failed, and on the opposite end section from the one that had a failure. This is why I think if I can descale it to some 20% of its current size (and not all the way to prevent any potentially weak spot there from springing a leak) and clean up the rest of the boiler in the process, after I institute water remediation this boiler will last a while longer. Maybe even decades.

If you don't have water loss, or any other issues with hard water, or with chlorides, this won't be an issue with a new boiler. We all know, from discussing it here on the wall, that new boilers have 2 physical negatives going on compared to old day boilers: new ones are cast thinner and with pins in the fire side of the sections for increased efficiency, and the cast iron metal quality itself is probably poorer (recycled metal vs. virgin ore used 40-50 years ago, requiring various additives to clean up the metal). So, these two factors bring water quality to the forefront, and I'm affraid the manufacturers have not caught up, or cared to. I can't get a straight answer even from the manufacturer on how to descale this boiler I have.

As to your oversized boiler, I see you are already going down the path of running on vacuum and vapor, in addition to downfiring. Is your boiler gas or oil? Sorry I'm asking - I've been reading your posts just missed this info.

If you have a way and the room to get a new boiler in your basement, and have it put together, header and all, and installed parrallel to your current boiler, this may give you an option to run your current boiler or new boiler, and have the other one as a back up. If I were you and was considering a new boiler but was hesitant because of quality, I'd do this. And then, test the heck out of your water.

Second thought would be to add some radiators to existing risers to match rads closer to the boiler EDR. Depending on where you get some used rads, this may be the cheapest option, esp. if you can do the work yourself. Might not be the most pretty or practical solution, but worth thinking about. I know, this may not be practical, but think about how quickly you would warm up the place, and how quickly the boiler would shut off. Then extra cast iron from the rads will keep the place warmed up on residual heat from the rad itself twice as long.

Good luck, and thank you for your comforting words regarding my boiler. I am disappointed the failure was so quick after the installation.

MilanD

@Koan

I wrote this long response, and now it's gone...

Let me try to recreate:

Our current 6.5 yo boiler has had 2 things going against it: 1. losing steam without me realizing this was bad, and 2. hard water 181 mg/L, with slightly elevated chlorides at 46 mg/L vs. < 30 mg/L needed.

So, after inspecting the boiler with the section off, I discovered only one more sizeable scale blister. This one was on the opposite end section, and below the water line. It is about 1/2 the size of the blister which caused the pinhole leak. I am hoping with some descling and reducing of the buildup down to, perhaps 20% of its current size and not more for fear of exposing some developed weakness/pinhole, and after cleaning up of the rest of the sections, this boiler will last for decades to come. Esp. after water remediation is implemented. At least, I'm hoping.

Which brings me to the folowing: It has been evident here on the wall, that new boilers are cast thinner and with pins on the fire side for improvement in efficiency. There may be also issue with, as some here have suggested, poor quality of casting iron, whether due to high recycled content and need for stabilizers vs. virgin ore used in the olden days, or some other reason These two facts, esp. with the pins on the fire side, have created a condition for overheating and failing of the casting section when scale buildup is inside the steam or water chamber.

So our final line of defense, after making sure system is tight and not taking excess amounts of make-up water, is water quality itself. Unfortunately, manufacturers for the most part don't care about it enough, and most installers don't either. Heck, I can't even get an answer as to how to descale the boiler from the manufacturer, so how to expect the tech knowing or wanting to do anything past install, for fear of owning the failure, should it occur after they worked on the system.

In your case, if your water quality is satisfactory, and if you have no abnormal loss of water, and if you have room in your basement, when the time comes to bite the bullet and get that new boiler while the current oversized boiler is still kicking, install a new one parrallel to the old one, pipes and all, and you can run the new one and keep the old as an emergency back up. Just make sure it has some steamaster tablets, or 8-way, or Rhomer additives to prevent rusting, and fire it from time to time to boil off any O2 absorbed.

On the other side, if you can source some used rads and can do the work yourself, you could add more rads to current risers. Heat will come on more quickly, you won't waste fuel building pressure, and extra cast iron rads will hold the residual heat longer, spreading burns farther apart. May not be that practical, but could be done for reasonable amount of money if you do the work yourself.

Anyhow, thank you for your kind words for our boiler. Yes, disappointment it is for me. 6.5 years should not be a norm, regardless of water loss or water hardness. Now it's off to making sure RO water is used, with chemical conditioners described earlier.

Koan

did your water become less boiler friendly?? I guess this could happen , but it seems odd.

MilanD

I never paid much attention to water quality, truth be told, until I realized we may have an issue because of the past water use and its negative effect on boilers, which I learned of here and from Dan's few books. Then, I looked. As in - a few months ago. We happen to have water from deep wells, basically, artisan water - city pumps if from deep aquifers. This water is extra hard - 181 ppm (or mg/L)... Great for people, not so great for steam boilers. With water loss and replacement water being brought in, this easily increases ppm or mg/L concentration up to very unhealthy levels when it comes to scale formation. Bummer for us, and for me, a realization of an unknown unknowns...

ps. Looks like my other comment showed-up.

MilanD

Descaling setup done. I'll be using Rydlyme. Test run with water first to make sure sump pump will be strong enough to act as a circulator. Will get a strainer to catch any larger debris should there be any.

MilanD

Ran 2 hours of 25% Rydlyme/water solution today. Refilled and drained the boiler 2x after descaling, filled and fired. Will need to do a few more draining - lots of suspended solids still in there. May wand it Gerry Gill style if rinse alone doesn't clean up all the particles, or try cooking it with lye first.

Here's a video of the setup while running:
"https://www.amazon.com/photos/share/LPLiWvqq0uicHxpuyhi6UkBqstL6ImtR5i0DbHUeSvV"

Steamhead

That is some nasty-looking water!

MilanD

Rydlyme is dark like grape juice... On the other hand, can be handled without any special equipment. It really looks like it scrubbed that boiler quite well. I'm going to try to stick a camera in there once I do a few more rinses. The plug on the bottom 4" is that "x" type (cored?), so I should be able to unscrew it with a breaker bar.

MilanD

Ready for wanding... had to build this thing and used some old 1/2" copper and a valve I had sitting around. A couple of NPT male/female transitions so it can be built to 6 ft+ to accommodate the entire length of the boiler plus equaliser return that sticks out. Sprayer nozzle was fashioned with a hammer out of a street 90.

MilanD

Wanding done.

https://youtu.be/uGKQwAFQD0A