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Importance of Relief Valve Piping!

Mike Bash
Mike Bash Member Posts: 3
I wanted to take a few minutes to tell a story about the importance of piping the discharge from relief valves to the floor.

Several years ago I went on a call for a second opinion on a job. I am not a boiler expert but went to see what I could do. They had a leak in the copper return line and someone said they would fix it. They cut the leaking fitting out and never came back. Everything sat drained all summer and of course it was now turning cold and they wanted heat.

I could not tell what it would take until I got started so they gave me approval to see what I could do. First I replaced the missing fittings and pipe. Next I started to refill the system. Immediately the relief valve started leaking. It must have been open and just stuck that way. Next I replaced that and started filling again. This time everything held.

Now to get the air out. As I stated before I am not an expert, Plumbing is what I do. So I did what I normally do. I did not have a way of purging the air other then just starting to bleed the radiators. Now how I usually do this if I am by myself is close the expansion tank valve, and crack the quick fill until it hits around 25psi. Then I start to bleed the air out. When it slows I go back and fill it up again. I think my first mistake was I cranked up the thermostat so I could keep track of how far I was getting heat. I just kept filling and bleeding and feeling the pipes to see if I was getting the heat anywhere.

It seamed I was getting close to having it start to work, I was getting heat most of the way around the basement. No remember the boiler is firing and the circulator is trying to pump all this time. I had built up the pressure again, walked around and felt the pipes, and before I went back up stairs to the next radiator I went back over to check the pressure one more time. I could not remember if I had filled it again this trip or not. I got about 7 feet away and I heard a loud noise. The relief valve blew wide open. It didn't start with a drip or any warning, just went wide open. The water and steam hit me square in the chest.

I had mostly second degree burns with some third degree from my belt to my chin. My heavy pants must have helped but my thin shirt did not stop anything. I am just thankful I didn't get it in the face. A few more steps and I would have been looking straight at it. Several days in the burn unit and many weeks off work will teach you an important lesson.

I do not blame anyone, after all I was the one who put the new valve on. The old one was not piped to the floor either or I would have used the old pipe. I should have not been so lazy and done it right. Anyway when ever you are around any appliance that has a relief valve and it's not installed correctly please point it out and have it corrected. A few feet of pipe can save a lot of pain and suffering.

Thank you for your time.


  • john_27
    john_27 Member Posts: 195
    thanks for the advice...we'll mentionit around!

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