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doesn't a Y strainer upstream of an F&T Trap impede it's T function?

archibald tuttlearchibald tuttle Member Posts: 682
edited January 11 in Strictly Steam
I'm replacing a couple Illinois 6Gs with Sarco inlines as recommended in my other thread over here and i never really thought about the illinois Y strainers that lead into these traps. they aren't blocked with junk, i've cleaned them a few times, but set as they are, don't they also function as traps and unless their geometry is more carefully calabrated than i can tell just looking at them it seems that there isn't really anywhere for the steam to make it through without forcing its way just under the water near the top of the screen?

Guess its good for the trap not to get junk in it that could lodge in a seat or fill the chamber so float doesn't drop but i'm concerned about good steam venting for the main (these connect the end of north and south mains to the returns) and then good closure once the steam gets there so i'm wondering if these Y traps are the right install, or maybe there is a Y trap that has a high port as well so steam goes over the top even while water goes through the strainer. obviously if it clogged up and backed condensate into the return then dirty water could spill over the steam relief, but that is a maintenance question vs. theoretical operation.

thoughts on necessity for strainer and pointers to alternative hardware if any.




  • archibald tuttlearchibald tuttle Member Posts: 682
    sorry, my camera has been a little fuzzy this week but i think this illustrates the set up
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,099
    I have often thought about skipping the trap strainer. Usually you don't find much debris in them, I don't think I ever had a call that turned out to be a plugged strainer.

    If valve are installed on the Y so they could be blown down it would be better but most won't spend the $$$$$.

    On cast Iron strainers fitters seldom use any never seize on the cap that you need to get of to clean the strainer. Try getting one apart after a few years...pretty near impossible there always jammed in a tight spot the cap is at 45 degrees and it's difficult to get wrenches on them with good leverage. You usually have to remove the strainer and pt it in a vise to get it apart.

    That's the end of my rant.

    There's always going to be water in the strainer basket. I don't think it causes any issue.
  • archibald tuttlearchibald tuttle Member Posts: 682
    edited January 13
    thank you for that rant! i love it. agree. when i get them apart they always get loving coat of mas loosener when they go back together. you are right, initial separation i had to take the wyes to the vice, but once i've had them apart I can use an 18V 1/2" impact with a 1 7/16" socket in this case.

    as far as the cleanout/blow down, i like the valve idea if you've got any pressure but is this really useful if i'm running under a pound of steam. i've got 12" brass plug so can try to physically clean, although once i get the major plug set up or reasonably easy removal, i have tended to overlook this distinction and go right to screen removal.

    it might be overkill, as you suggest, not just because of $$$$ but given the limited amount of sediment collected as i've monitored these for 20 years in very low pressure steam anyway (not annually, maybe every 5 or so). I'm think to myself that what i've seen wouldn't really clog up the F&T trap anymore than the occasionally necessary dismemberment and cleaning could take care of. similarly, i like a coat of non hardening silicone paste on the gaskets of the F&T trap so they don't stick and break every time you open it (or curing high temp silicone if they haven't been prophylactically treated and the gasket fails and i ain't got another)

    while i agree i haven't had water hammer with this setup, i'm still mystified on whether i'm getting good steam venting in the mains. although, ironically, i'm replacing the traps because I think the thermostatic elements aren't closing any more and i am losing a little steam at the end of the runs into the returns and i'm wondering if this is contributing to my difficulty in quick reliable steam to the radaitors right near the end of the main.

    it would take micrometers to figure if there really is any air space above the trapped water for the steam to get through the Y strainer, but one friend who is a recovering heating help addict suggested i swing the trap to like 45 degrees off vertical which would raise some of the upper end of the screen above the weir so that might be a compromise. my other thought was just to drill a 3/8" hole at the top of the center baffle to provide a steam pathway separate from water. or, as you suggested, just leave it out of the updated install.

    obsession over/

  • DanHolohanDanHolohan Member, Moderator, Administrator Posts: 15,005
    edited January 13
    Old-timer trick: Pipe a thermostatic radiator trap on a bypass above the F&T. It will pass the air around the F&T and close when the steam arrives. It won't have to deal with any condensate.
    Retired and loving it.
  • archibald tuttlearchibald tuttle Member Posts: 682
    this is getting scary - am i an old timer cause i already thought of that?

    i guess i just felt like that's a couple extra tees and union and make up and a thermostatic trap when i'm already buying a thermostatic trap in the F&T and then i have to still maintain two thermostatic elements. and i'm thinking a straight float trap is not a common alternative if i were to use the two separate trap approach.

    so what do you think about my 'new timers' trick of drilling a 3/8" hole through the baffle just inside the 'top' of the run of the Y strainer?


    PS - AHR this year?
  • DanHolohanDanHolohan Member, Moderator, Administrator Posts: 15,005
    Worth a try, Brian. And yes, I'll be at AHR with Erin and Marianne.
    Retired and loving it.
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