The case of the steam filled room. this Friday's case

RayWohlfarth

The telephone call should have prepared me for the service call but I didnt listen. The owner said the pop safety valve on his boiler would open every once in a while. The owner replaced the pop safety valve and the problem persisted. A few hours later, I found myself inside a steam filled boiler room in an attempt to stop the burner. Steam displaces oxygen which make breathing difficult. In addition, steam can find its way inside electrical panels and cause shorts. To say I was nervous was an understatement. After stopping the boiler, I was able to figure out the cause. Bet you already know. I will give you a hint in the picture. The answer and the video will be posted on Friday morning at 6am

retiredguy

This is probably the case of the plugged pigtail. When I was still working we never allowed 2 pressure controls on one pigtail and that includes the modulating control.

Sylvain

retiredguy said:

This is probably the case of the plugged pigtail. When I was still working we never allowed 2 pressure controls on one pigtail and that includes the modulating control.

Indeed, process control and safety should not have a common mode of failure.
If possible, different tapings and different technology.
Unless i am wrong, I don't see a safety pressuretrol which needs a manual reset.
If the pressuretroll on the left is for safety, it should be set lower.

Steamhead

retiredguy said:

This is probably the case of the plugged pigtail. When I was still working we never allowed 2 pressure controls on one pigtail and that includes the modulating control.

Sylvain said:

retiredguy said:

This is probably the case of the plugged pigtail. When I was still working we never allowed 2 pressure controls on one pigtail and that includes the modulating control.

Indeed, process control and safety should not have a common mode of failure.
If possible, different tapings and different technology.
Unless i am wrong, I don't see a safety pressuretrol which needs a manual reset.
If the pressuretroll on the left is for safety, it should be set lower.

This.

RayWohlfarth

I knew you guys would get it right away. I was more curious if you've ever been inside a steam filled boiler. It's a scary and disorienting experience. I guess what upset me the most was that I didnt follow my rules. I usually prop open the boiler room doors and shut off the burner until Im sure the room is safe. I didnt do that on this one. Have a great weekend all. Here is the link to this weeks video.https://www.youtube.com/watch?v=Zm6s7Sdzt3Q

retiredguy

@Ray, on Christmas Eve I was called by the answering service for an emergency call to go to the Shenango High School near New Castle because of no heat due to a power failure. The hot water boilers were fed with soft coal using Auburn coal stokers. With coal, the fire does not go out like it does with nat gas or fuel oil so there was a large fire still burning and the school people were afraid that the boiler would overheat. By the way, these 2 boilers heated both the high school and the elementary school so you know that these boilers are pretty big. Everything shut off except the burning coal. I got to the job, went into the boiler room, studied the situation, went up the ladder to the catwalk to continue my observation. Just then the relief valves lifted filling the boiler room with steam from the super heated water with a temperature about 230 degrees. There was no breathing in that atmosphere. I jumped to the floor to escape the steam which you know you can't breath. Everyone outside thought I was dead and called for an ambulance. I walked out of the building about 10 minutes later when I heard the siren of the ambulance. Everyone panicked except me since I knew how to cope with the steam cloud.

RayWohlfarth

Wow you're so lucky to be here. That could have ended badly. Glad you had your wits about you. So I guess there's no quick shutoff of coal. Thats kinda scary I appreciate you letting me know

mattmia2

Maybe close the door behind you and go looking for the main breaker or gas meter in another room or outside?

mattmia2

does the coal at least have a control that closes off the air supply if the power fails? Seems like that needs to be there if it isn't a gravity system.

Intplm.

Oooh. @RayWohlfarth
Sometimes you have to dress like a MLB catcher in a boiler room. Steam filled or not. Ouch. Been there done that.

retiredguy

On a large coal fired boiler that suffers from a power failure the fire dies down but does not go out. The coal will still heat the boiler but a very reduced rate. On this unit the hot water circulating pumps also shut off along with every thing else but the coal still produced heat. The water in the boiler continued to heat until the pressure reached 30PSI, (275F), the setting of the relief valves. When the relief valves lifted the super heated water instantly flashed to steam.

RayWohlfarth

@Intplm. Yes sir You never know what the previous knucklehead did

ethicalpaul

We should strive for accuracy. A steam-filled room would be invisible and would cook you very quickly. The room was full of condensed aerosol water droplets

Intplm.

I once went into a very large mechanical equipment room that serviced a quarter million square foot facility.
Working late after a shut down there was an explosion of sorts. The entire mechanical room was engulfed with steam.Yes, steam. I was tasked with going in and shutting an eighteen inch main gate valve off because I new the area well and because I took care of that particular room.
After shutting the steam off and the area was clear of steam it was found that a condensate return tank had ruptured. The Hartford Steam Boiler insurance company was called in later.
Having a clean well kept uncluttered boiler room and knowing your surroundings, having no trip hazards made this a safe, or safer task.
@RayWohlfarth , I didn't have to walk like Frankenstein but it sure felt funny.

RayWohlfarth

@ethicalpaul Thanks for clearing that up. It sure felt like steam LOL
@Intplm. Good for you. It is a scary situation

ChrisJ

Steam is a substance containing water in the gas phase,[1]: 7  and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Steam that is saturated or superheated (water vapor) is invisible; however, wet steam, a visible mist or aerosol of water droplets, is often referred to as "steam".[1]: 6 


https://en.wikipedia.org/wiki/Steam


Also of interest
https://en.wikipedia.org/wiki/Sauna

ethicalpaul

Yes, it is often incorrectly referred to as “steam”, I agree

Steam that is saturated or superheated (water vapor) is invisible; however, wet steam, a visible mist or aerosol of water droplets, is often referred to as "steam".[1]: 6 

That's strange because the steam that my boiler makes, even though it is by definition "wet steam" (as is all steam created by residential boilers), is completely invisible.

Working late after a shut down there was an explosion of sorts. The entire mechanical room was engulfed with steam.Yes, steam. I was tasked with going in and shutting an eighteen inch main gate valve off because I new the area well and because I took care of that particular room.

That sounds scary! Were you holding your breath or did you have breathing apparatus?

Intplm.

ethicalpaul said:

Yes, it is often incorrectly referred to as “steam”, I agree

Steam that is saturated or superheated (water vapor) is invisible; however, wet steam, a visible mist or aerosol of water droplets, is often referred to as "steam".[1]: 6 

That's strange because the steam that my boiler makes, even though it is by definition "wet steam" (as is all steam created by residential boilers), is completely invisible.

Working late after a shut down there was an explosion of sorts. The entire mechanical room was engulfed with steam.Yes, steam. I was tasked with going in and shutting an eighteen inch main gate valve off because I new the area well and because I took care of that particular room.

That sounds scary! Were you holding your breath or did you have breathing apparatus?

Synonyms seem to be the case here.

I walked in as steam was flowing, vapor was emitting, white mist was floating and minute water droplets were all changing state.
I was both chastised and heralded for my actions.
I was a young kid, (in my twenties) was oppressed upon by an engineer to go in.
My lesson learned after this was how to say "no" and how to say it cooperatively. As well as other communicative subjects with out taking or giving offense.
I'll never forget it and hope that I maintain its practices.