Fand T trap return piped to to flow up 16" ????

steampunknoob

     I have a F and T trap model #11T made by Strong.  Can you pipe a return line up out of a F and T trap?????

     Years ago someone installed this at the end of a main line steam branch. The return outlet is piped to run up about 12" to 16" up to connect with other radiator return lines and I suspect this is a cause for some of the water hammer and radiators heating slowly (I still have a lot of other parts of the system to check though).  I just know the basics of steam systems, I'm learning as I go.

     Would it a Inverted Bucket trap work in it's place? 

copperkid

You can pipe it that way

depending on steam pressure.  It takes roughly 1 lb of steam to raise condensate 2 ft or so.  Their are other variables to consider, but installing a check valve after the trap is a good practice.  You might get some noise with the check opening and closing but if you have a constant pressure on the line it should lift it.  If this is a gravity return system you generally don't want to lift condensate, if you can repipe it to drain by gravity.  I have seen too many unit heaters not heating because they tried to lift condensate, these had modulating control valves which was the main reason for backing up.  The valves modulate almost closed and their is not enough pressure to lift the condensate, the units would get water logged and hammer. Just my thoughts

Pumpguy

As copperkid said....

If you have enough steam pressure available, it can push the condensate up to the return line.  On the other hand, it would be best to re-pipe this return lower for a gravity flow down to the existing returns. 



If that's not practical, and you want to heat with the lowest possible steam pressure, you could install a small condensate pump receiver, allowing the draining condensate to flow by gravity down to the receiver, and then pumped back up to the higher return line. 



If this is a 2 pipe vacuum return system, installing a lift fitting at this trap's outlet would also work to lift the condensate.



Hope this is of some help to you.

steampunknoob

re:

Thanks you guys. I figured it was piped wrong but just wanted to make sure. I have a two pipe gravity return on a large low presseure steam plant system. The maintenance has been neglected for years. Im going through all the traps now and making a map of the maze of steam lines and returns to identify issues. This was something that caught my attention. The ceiling has been lowered only about 8 inches in this room and this radiator was added in the room above later and they piped the trap below the lowered ceiling instead of raising the steam leg up aabove the level of the return 6 inches off the original ceiling height. The system use to run about 7 psi and I believe is also oversized for this buildi g so I want to get it running at about 1 to 2 psi if possible. Since I lowered the operating pressure on the boiler to try and save fuel, boiler cycling and etc... to 3 or 4 psi, I think the trap in question is now flooding trying to raise the condesate to level of the other returns. I believe I have room to repipe this trap to a return discharge level above the other return piping just slightly. I just wanted an understanding of the situation and possible fixes before having a maintenance man go thru the trouble of repiping. I also had read an inverted bucket trap could raise condesate a few feet at low pressures w/o changing the system. I appreciate every ones input, this newbie is learning alot! I hope to have this system hummming next year, efficient, effective, low cost, quiet and comfortable, (high speed, low drag as they say, lol. ) [image of trap posted sideways, rotate right]

Steamhead

Not sure from the pics

but if you can drain by gravity from the steam main level before it turns up toward the trap, you need an inline F&T trap for this job. This type of trap has the inlet and outlet at the same level. Use an eccentric reducing coupling to get the steam main piping down to 3/4" or 1" without creating a water pocket, then mount the trap. At the moment, you have a massive water pocket and that's what causes the banging.



Here's a pic of one, a Sarco FTI-15. Disregard the dip in the piping after the trap, it only serves as a swing joint to let the underground main expand and contract. This trap doesn't need to vent air but yours does, so don't install a dip.



However- where does this return line go? Does anything else connect to it between the trap and the boiler room? What happens when it gets to the boiler room? If the answers are correct, you may not need a trap there at all.

copperkid

Yeah, does the main jump up?

There might not be a need for this trap usually we trap a main when their is a long horizontal run, or when it rises up.  Or finally at the EOM  end of main,or on a boiler header   You mentioned this was a branch if it is short enough you could back pitch it to the main being that your onlyy running a few pounds.More pics would helpm  I've seen alot of fitters pipe things, especially steam wrong I'm sure you'll find more things.