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Killing my boiler

This post was inspired by the article entitled , "How to kill a Boiler", Published: July 18, 2016 by Dan Holohan.

When my boiler and I met, she was about 45 years old. I have been the proud caretaker of the old girl for the past 30 years. She is now 75 years old, and still the only girl for me.
She is a simple girl. Just one pipe, no Hartford loop, no drop header, and no auto fill. She gets fired up, cuts out at 1.5, and cuts back in at .5lbs. Everything upstairs has always been quiet, and toasty.
A few years ago I began to notice that she was drinking more fresh water than usual. It did not seem like a real lot more, but definably more than I was accustomed to giving her.

I really don’t remember exactly how it happened. But It was pointed out to me that there was some water on the floor. It was behind her. Where I did not ever notice it. It was also being very quickly evaporated from the heat that surrounded her.
But there it was. a drip, drip, drip. It was coming from the very bottom of the dry return. All the way in the back, and all the way at the bottom. Right where the return connected to the boiler.

Then, like a miracle, from this steam web site, came Mr. Matt Sweeny (aka Mad Dog). Somehow, he managed to get access to, and cut out, the offending nipple. And then re-pipe the whole thing in brand new black iron. Leak stopped, boiler saved.
To this day I look back behind her. I look at the dry floor. I can see the new pipes that Matt installed. But what I am really seeing, is a work of art That's what it looks like to me.

So, why this long story.
I don’t remember how long I was adding excess water. I did not notice the drip, drip, drip. It could have been a few seasons. But I did notice a powdery white substance showing up on various parts of the old girl. It was some kind of corrosion, and it was showing up on some of the valves. In some places, it was forming, what looked like stalagmites.
Once Matt fixed the leak, The corrosion stopped. Or a least did not ever get any worse. I am still just a rookie, but I am pretty sure the leak, the adding water, and the white powdery corrosion, was all caused by the fresh water.

Well, once again the fresh water is going in. This time it’s a lot of fresh water. This time the leak is much faster, much worse. about 2 gallons a day. This time it’s the Low water cut off.

The LWCO is about 7 years old. It came with, and was installed with, a cork gasket. Very soon after it was installed, I noticed that the white, powdery, corrosion, had formed on the gasket. It did not seem like it was that bad. I also thought that it would stop getting any worse, because the leak was fixed, and that put an end to any further corrosion. Wrong, wrong, and wrong.
The cork gasket never stopped corroding away. It just kept getting worse, and worse. I just left it alone, I did not touch it, and it was dry. Not leaking.

A couple of days ago that all changed. I noticed a little pile of white powder on the floor. Directly under the gasket of the LWCO. Then, a few days later, the leak began. The pile of powder was gone, and replaced by a bucket. Currently collecting about 2 gallons a day from the drip, drip, drip, of that failed gasket.

I am now adding two gallons a day of fresh water back into the boiler to make up for the loss. I have been told that the cork gasket is "no longer available". I have been told that the new gasket is an "O" ring. I was also told that this was a "common problem", and that's why they got rid of the cork gasket.

So, now I need the entire unit. The new one will have the "O" ring gasket. But, my biggest problem is getting the old LWCO off. It is attached with eight, 5/16 bolts. All of them are corroded, and rusted, beyond belief. Photos are attached.

I was told the heads might snap off. It looks to me like that is going to happen. I was told "drill, tap".
I was told "maybe". When I asked "what happens if the bolts do snap and the "drill and tap" is unsuccessful"
I was told "you will need a new boiler".
Well !
After all this boiler and I have been through. No way I am going to let a "safety device" stop us from ever seeing each other again. No way. I'm not breaking up this way.
There will be a day when I see the white smoke. But until that day, nobody is going down into my basement with a sledgehammer.
Even with this massive leak. She is still nice and quiet, and still keeping me toasty warm upstairs.
Today I am making a phone call. It's time to bring in the big guns.
73 year old one pipe system with original American standard boiler, oil fired becket, 2 inch steel pipe main, 100 feet long, with 8 radiators above.


  • retiredguyretiredguy Posts: 161Member
    By the way, that McDonald Miller low water control is a model 69. The repair kit is a #6667. Looking at the condition of that control, I would opt for the complete control since the approximate price is almost the same and the whole control will give you the complete replacement if the bolts snap off during disassembly.
  • clammyclammy Posts: 2,416Member
    U could add any 67 lwco to your sight glass assembly and completely remove that low water cut off body and then plug the opening . I assume your on oil ? I know your going to keep her cause you love her but a new oil fired boiler would likely consume about 1/3 the oil then your girl . Just saying . Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • SteamheadSteamhead Posts: 13,564Member
    The entire housing of that LWCO screws into a 2-1/2" tapping in the boiler section. I'd completely remove it, screw a 2-1/2x3/4" bushing into the boiler and put a probe-type LWCO in the bushing. No moving parts, no gaskets, and much easier to service.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 6,505Member
    If you go with a probe type low water cutoff you will have to do some rewiring.
  • SteamheadSteamhead Posts: 13,564Member

    If you go with a probe type low water cutoff you will have to do some rewiring.

    Worth it IMHO.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • coolfx35coolfx35 Posts: 35Member
    She is a leaker.. 2 gallons a day? Must be a huge leak above the water line.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 6,505Member

    "She's a leaker mama"

    You don't happen to be a fan of a certain U tube plumber do you? LOL
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