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First Start-Up; need some help

Ok, I just fired up my two-pipe vapor system after doing some major system improvements: all new radiator traps, new cross-over traps, new main vent, and I replaced the horizontal piping under the pressurtrol and gauge. About 10 minutes in the vent was hissing wonderfully. Started making steam 17 minutes in. Ran around, all radiators getting warm. Main vent slowed quite a bit (good sign), then we started to register pressure. Pressurtrol kicked the burner off at about 1.5 lbs, and back on down at .5, consistent with my settings. All wonderful so far. After pressurizing, the Trane Direct Return trap started clanging. I then noticed water leaking from some of my connections on the cross over traps. I then felt the return pipes; they are all hot. Yikes! I am now at 50 minutes after starting. I shut the burner off about 10 minutes ago. The main vent is now mainging a throbbing, groaning hum/noise, and the outboard check valve is clicking. 6 lbs of vacuum at the gauge. What does it all mean? Maybe this is all good (the hot returns can't be a good sign...)


  • MotownSteamer
    MotownSteamer Member Posts: 110
    hold on a mintue!

    The groaning is not coming from the vent...it's coming from this tapping at the bottom of the boiler! It's the horizontal pipe to the right of the LWCO discharge pipe. What is it? Why? Could it be a reason for the steam in the returns? Photos for now, but I'll have a link to a YouTube video in a couple minutes.
  • MotownSteamer
    MotownSteamer Member Posts: 110
    ok, here is the video link

  • moneypitfeeder
    moneypitfeeder Member Posts: 249

    Didn't the Trane systems need to operate at really low psi's? If its the system found in LAOSH it was supposed to be set between 1 to 6 ounces of psi. If so, you might need a vaporstat to start, and crank the psi down to ounces.

    Also per LAOSH if a crossover trap/air vent between the end of main and dry fails you get steam in the dry return. You can't get stem into the rads then if there is steam in the dry return.

    Side note, higher pressures can damage some of the older traps or cause them to not work till the pressure is reduced.

    I've got a 2 pipe vapor sys. w/return trap & air elim. a lot of issuses settled down and the house heats faster with 0 to 1 psi. You'll want to add a low psi gauge as well to monitor it, the standard gauge won't even move that low.
    steam newbie
  • MotownSteamer
    MotownSteamer Member Posts: 110
    I agree, the pressure needs to be lower

    Thanks Dee, yes...it dawned on me last night that a vapor system needs to be cranked down. I just went as low as I can on the p-trol. The new boiler will have a v-stat. My contractor was just over and clarified to me it is normal to have warm returns, so I may not have a problem. I still need to know more about the DRT, but looks like I'm headed in the right direction
  • Dave in QCA
    Dave in QCA Member Posts: 1,785
    edited October 2011
    Trane Publication

    Here is a link to a booklet full of descriptions on various Trane vapor system components.  http://www.heatinghelp.com/files/articles/1392/26.pdf  

    You may have already found it, but if not, enjoy!

    I suspect the clanking in the Trane Return trap may be normal, depending how loud it was.  The device does cycle open and closed when there is enough pressure to prevent gravity return.  I have not seen one in operation but would imagine that it would not be silent.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • MotownSteamer
    MotownSteamer Member Posts: 110
    Awesome literature!

    Thank you Dave, I have not seen the Trane manual. Very helpful! I am now understanding the DRT. The consensus still seems to be that a vaporstat will essentially make the DRT a lonely fellow.

    I'm still wondering whether my returns have steam in them. They get warm, well...hot, but not until after the radiators heat. Nothing seems locked up. Could be condensate? "Lost Art" mentions returns getting hot after the mains heat.
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