Need advice on a steam hammer fix

nate70500

So I've found the cause of the steam hammer I am getting in my house, there is a sagging section of pipe in my crawlspace. It is the section right in the middle of the run. The section from my main to the crawlspace is pitched properly, as is the section from the baseboard radiator to about 4 feet from the wall of the crawl space (see attached diagram). I attempted to re-pitch the pipe properly, but I can't pull the far end of the pipe by the baseboard radiator any higher as it is against a floor joist (I can't cut into it due to it being the last joist and the pipe intersecting with it near the middle, I had an engineer look at it). And I can't lower then end by the boiler because that would require shortening my main which would make it too short. So I had the idea of completely removing the baseboard radiator (since technically its not meant for steam), taking apart the pipe at the 45 elbow where it goes into my crawlspace, and just piping it right up through the floor there on the opposite wall from where the baseboard is located currently and replacing it with a regular radiator. The section of the pipe from the boiler to the crawlspace is properly pitched so it should eliminate the steam hammer. Is this the best option? Would there be any issues doing this?

Jamie Hall

Before you do that, is there any hope of just lifting the sag? You'd be surprised how much give there is even in fairly large pipe. Add hangers. Or is the overall pitch (end to end) bad? Keep in mind that ideally (one pipe steam?) you do need 1 inch in 10 feet -- but unless you are really up against the limit in pipe size, you can get away with less (oh! Heresy!) provided the slope is absolutely even.

JohnNY

I'm not following this description 100% but it sounds to me like you need an arrangement of piping to accommodate a change of elevation. That means a vertical offset and drip line back to the return.

nate70500

> @Jamie Hall said:
> Before you do that, is there any hope of just lifting the sag? You'd be surprised how much give there is even in fairly large pipe. Add hangers. Or is the overall pitch (end to end) bad? Keep in mind that ideally (one pipe steam?) you do need 1 inch in 10 feet -- but unless you are really up against the limit in pipe size, you can get away with less (oh! Heresy!) provided the slope is absolutely even.

Yes it's one pipe steam. I removed all the hangers and tried to re pitch the pipe. No matter what I did the best I could do was make most of the run level, not pitched. I can't re pitch the first section of pipe coming off the main in the basement, it just doesn't move.

nate70500

> @JohnNY said:
> I'm not following this description 100% but it sounds to me like you need an arrangement of piping to accommodate a change of elevation. That means a vertical offset and drip line back to the return.

What is a vertical offset?

JohnNY

It’s a change in elevation that traps condensate which in turn forces you to provide some means of egress back to the return. It’s usually pretty simple.

nate70500

> @JohnNY said:
> It’s a change in elevation that traps condensate which in turn forces you to provide some means of egress back to the return. It’s usually pretty simple.

So basically add a loop into the line with a 1 inch difference between the line from the main and the line going to the radiator?