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Boiler was making a banging sound......

delta T
delta T Member Posts: 884
(Last call today, after hours)

So I went out to check on it and found the water to the boiler turned off, the relief valve was run to the drain with a rubber washing machine hose (this was so brittle it snapped of when I bumped it), and the inside of the hose completely plugged with rust. Not looking great so far. Boiler is cold (HO turned the thermostat off when it started making noise) so I open the valve and let the feeder start filling the boiler up. As it is filling I look around and start noticing things.

The boiler is 300kbtuh input peerless CI about 35 years old (of course the house is only about 1800 sq ft). 10 inch draft diverter, reduces to 8 inch and goes over the top of the cinder block wall. I follow it and find an 8 inch pipe sort of set below and a little off to the side of a 10 inch b vent flue (no attempt at sealing this connection, no....not even duct tape).

I looked in the burner chamber and saw a hole rusted/burned through the back of the fire box.

The system at this point is still taking water through the feeder. Boiler pressure gauge reads 25. I get my gauge from the truck and it is at 8 psi. I have to guess that the boiler was near empty.

So to sum up, this boiler had the potential to leak massive quantities of CO, light the house on fire, and explode all in one go.

Boiler is disabled, I will be sending a quote for replacement tomorrow.

Still shaking my head in awe at how scary this was.


  • BobC
    BobC Member Posts: 5,481
    I'm only a home owner but I have seen worse. It really amazes me at what people put up with and how little they know about safety.

    Many years ago I was sitting in the bosses office talking about what design approach to take with a job. While we were talking the receiver came in and said they had dropped a drom of paint thinner and it was leaking badly. The boss told him to use a shop vec to suck up the paint thinner.

    I told the guy DO NOT GO ANYWHERE NEAR THAT WITH A SHOP VAC, sop it up with absorbent and put it in barrels outside. My boss got upset and we proceeded to argue about it while the guy looked on with a dazed look.

    I told the receiver if he used a shop vac the result would be an explosion and he would be held responsible when I reported his actions to OSHA. i was on the safety committee and had the technical background for this kind of thing.

    I explained to my boss that shop vacs use universal motors with brushes (that spark really well) and they use the airflow to cool the undersized motors. The result would be a really good flame thrower.

    He agreed with me, This man was a brilliant engineer but there were area that he just was not conversant in.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
    delta T