Multiple Steam mains to 1 Sarco trap ? on a 2-pipe dry system

mstrbill

I dont know if this is correct , but i was asked to balance the steam in a large house that has a 2 pipe system with a dry return setup back in the boiler room when the 3 steam mains [ each larger than the next ] join together to 1 Sarco FT-15 than vented and dripped to the boiler return loop. My question is how can i speed up the steam flow to the smaller main when they are all joined in the boiler room to make 1 dry return. The mains are 1 - 4 " , 1 - 2-1/2 " , and the 2 " which seems to get the steam last . The owner wants me to zone it , and he can afford it , but i would like to understand the Joining of the 3 returns first . Is it right? the boiler is new , Sarco is new , we are pumping 1160 Sq.feet of steam , and the owner is not happy with the one 2 inch line to his side of the home /office. Should i install seperate FT traps for each main and how can i zone it properly , he can afford it .

Boiler wrestler

End of main vents

Is there a boiler feed tank on this system?

 Each main should be vented separately, but not necessarily trapped.

I love it when they can afford it.

mstrbill

return tank

no return tank

mstrbill

trapped

whats wrong with the main FT trap

Dave in QCA

f&t trap

Is sometimeused at the end of a steam main when it is connected to a condensate tank.  The purpose is to allow air to vent and to allow condensate to pass through and to stop the steam.  The application for a situation where there is pressure in the steam line and no pressure in the return line, such as would be the case when flowing into a condenstate receiever that is vented to the atmosphere. 



If the returns are dropping and becoming wet returns and flowing back through the hartford loop and into the boiler, then it is not connetect to an atmostpheric pressure condition.  The condenstate will flow by gravity back into the boiler because the pressure in the steam main is nearly the same as the pressure at the return connection of the boiler.



What does need to be taken care of is venting.   There needs to be a good sized or a couple good sized vents on each main unless each main has a crossover trap.  A crossover trap is pretty much a radiator trap that has the inlet connected to the end of the steam main and the outlet connected to the return piping. 



The end of the steam mains should be vented before they drop and the should not be connected until they are lower than the boiler water line.



Zoning is a very problematic undertaking.   It will cause a whole hoste of problems that would need to be very carefully addressed.   Do not go this direction to correct problems that already exist.  Fix the problems first.





Can you take some pictures of the piping, the boiler and its close piping, radiators, traps, etc.

mstrbill

more info

I said in my first post I have 3 steam mains returning to the boiler room  and then tied together and piped to the Sarco FT , then vented w/Hoffman 75 , then one pipe from the Sarco to the hartford loop . The whole setup has a good 40 inch B dimension. Should i just increase the number of main vents on the slower main and seperate the mains since they are piped together  before the Trap , maybe there is no lower pressure due to the other larger main returns getting there first , due to there size . 

Boiler wrestler

F&T

F&T trap not needed. Only end of main vents on each of the three mains. Adjusting the venting on the mains is a good place to start.

Steamhead

Basic problem here

is that three mains are going thru one trap. This is wrong- if you're using traps, each main needs its own trap.



But I suspect all you need to do is drip each main into a wet return and vent it properly. In this case the traps are not needed.