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Buffer Addition



  • scott markle_2
    scott markle_2 Member Posts: 611
    Mixing after the buffer

    You will be glad you did it this way, take a look at the tekmar 2 wire tn2 stuff (house control series) its not all that expencive and does a lot, (you will also need an wiring center to acomodate more than 4 zones)

    I don't think the return temp on the indirect is that big a deal because the tank is generally kept around 120, the Viessmann boiler I recently used can tolerat 120 returns, I wish the esbe valve could go a bit lower than 140.
  • PeterNH
    PeterNH Member Posts: 88
    The ESBE

    I've picked out is 113*. It is fully open at about 132.  This is said to be the best match for oil.


    I believe the 140* one that Tim has is better suited for natural gas boilers.


    I've been looking at the tn4 42x series.  422 and 346 and 444's.

    Gets expensive quickly.

    The tN2/400-401 plus 315, is lower cost, but the way i understand it, i would need to replace all existing 8 thermostats with tN2's.

    Ends up costing near the tN4 stuff. 


    Still researching the situation.


    I knew you'd be happy with the post buffer mixing.


    Any thoughts on a 4 way valve vs the injection pump?


  • PeterNH
    PeterNH Member Posts: 88
    edited March 2012
    Need Help Please

    And advice from those in the know.

    The buffer project has hit a major snag.

    When taking a close look at existing piping, i've found something that has stopped me cold.

    About 10 years ago, when i built the model railroad room and addded heat to it, the porch and the garage, the plumbers that did the work used 5/8" Wisbro HePex, to run to the baseboards.

    Sadly they also used Copper Bell Hangers to supoort the pex in the cellar.

    Upon looking at the pex in the hangers, i now see where the oxygen barrier has been rubbed loose and is off completely around each bell hanger.  About 1-2 inches at tech hanger is affected.

    After reading this thread:


    I am worried sick.

    What to do?

    a- replace all the old pex and use new hangers.. (diffficult and time expensive)

    b- Use heat exchangers and more pumps and expansion tanks? (two defferent  temperature zones are involved.)

    c- Use some sort of chemical additive?

    d- Don't worry, do nothing and leave it as is?

    The final plan was just about ready and the work was about to start..

    But know things are on hold until i can resolve this mess. 


    Thanks for any and all advice,

  • scott markle_2
    scott markle_2 Member Posts: 611
    Barrier tubing


    I would not be overly concenned about this. I disagree with the migration at the cuts therory as it relates to the onyx, I believe the onyx is just a bad product, yes it's better than entran 2 but aside from ease of use why would anyone chose expensive rubber with a history of problems as opposed to pex.

    As rob points out not all pexl barriers are on the outside of the tubing (can you document this rob) if I was going to make a guess I would say that uponor he is probably infused with a barrier and this is why it warns against use with potable water all over the tube. There is a rumor that this is only because they didn't want to pay for the NSF certification, I don't buy it, they sell millions of feet of tubing it would be a huge convienience to be able to reuse radiant scraps in potable applications and I believe that if it could pass NSF they would be doing their customers a disservice by not getting it tested.

    Viega barrier has approval and every time I use a scrap for a water line I get a warm fuzzy feeling for the thoughtfull Germans, when I toss my uponor he scraps the feeling is reversed. If they are realy too cheep to certify it, or they just want to sell more tube by forcing wast... is this the kind of company I want to do business with?

    I'd put some Rhomar 922 or Fernox in there, order up your tekmar 402, wiring center, and 527 stats and be done with it, btw- I like mixing valves too, a three way valve is all you need, it will mount up very nicely and be supported by the stout pipes on the boiler buddy.
  • PeterNH
    PeterNH Member Posts: 88
    Good to

    Hear from you Scott and thanks for your thoughts.


    Sounds like a plan, i'll go with the chemicals.

    I thought Rob was talking about pex al pex where the aluminum is in the center.

    What i'm seeing is certainly a thin loose layer, kinda like pvc film.

    I'll try and get some pictures.

    Clearly it has been like that for a long time and so far nothing in the heating system seems to be broken.  

     "or they just want to sell more tube by forcing wast... is this .."

    My money would be on the sell more tubing bet.




    I like the mixing valves too, but certainly with the valve, and a motor, is many times more costly than an injection pump.. humm..


    The wierd hot weather we had the last two weeks, (until yesterday)

    forced a halt to the project as pressing outdoor needs took control.

    Along with book keeping, tax time PITA, time consuming stuff..


    Now it's almost back in full to to the buffer project.

  • PeterNH
    PeterNH Member Posts: 88
    edited March 2012

    The final plan. 


    Maybe a few minor changes.

    As far as major changes go..->(speak now or forever hold you peace :-)

    Parts are under acquisition.

    I'll try and get some pics posted, "real soon now."


    Thanks to everyone for all the help,

This discussion has been closed.