what are these steam traps that are not on rads?

rhodebump

I just noticed that there are a couple of these steam traps that are not on a radiator. I don't understand how they should work. The trap is positioned like on the top of a hill, so not very much water would get to it.
One end of the trap is the condensate line, and this condensate goes into a wet return.

Here is the outside (where you can see the trap). The pipe below is a condensate line that goes into a wet return (a vertical pipe that drops below floor grade)



Here is the where the other side of the trap goes to:



From what I can tell, this also turns into a wet return. (a vertical pipe that drops below floor grade)

I sincerely appreciate everyone's help on this forum.

-Phillip

nicholas bonham-carter

Maybe a crossover trap, which vents the supply main into the dry return, from which the air then goes to a special vent. Often these special vents contained a one way vacuum disk, which prevents the air from getting back into the system.
If it is functioning properly, the main side should be steam hot, and the discharge side should only be condensate hot at most.--NBC

Steamhead

nicholas bonham-carter said:

Maybe a crossover trap, which vents the supply main into the dry return, from which the air then goes to a special vent. Often these special vents contained a one way vacuum disk, which prevents the air from getting back into the system.
If it is functioning properly, the main side should be steam hot, and the discharge side should only be condensate hot at most.--NBC

This.

That looks like a Dunham trap. The steam goes into the side of the trap and the air comes out the bottom. The line from the bottom connects to the "dry return"- follow this to the boiler room and you should find the air vent. if you're not sure what the air vent is, take pics of any devices in the piping adjacent to the boiler and post them here- we can ID them.

This is a Vapor system- the Cadillac of heating in its day, and still one of the best out there.

dopey27177

This steam trap is the main vent for the steam main.
After the system air is removed from the steam main the trap closes and the steam main pressurizes.
If the element in the trap is defective steam will leak or flow into the return and pressurize the return. when that happens steam will flow to the radiators and stop steam from entering the radiator from the steam supply pipe Because the steam pressure is equalized in the radiator. Additionally series banging can ocuur in the radiator and return piping,

Jake