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Boiler piping opinions

OhioboilerOhioboiler Member Posts: 6
edited December 2019 in THE MAIN WALL
Hi, does this look right? I think the pump should be moved to between the air separator and the manifold (does it matter if vertical or horizontal?). The installer originally put it between the dirt magnet and boiler, but I told them I designed it to pump away. It’s a Noble 110, with alpha2 pump to cast iron rads, each equipped with TRV. Any other things I should look at? They had never put a home run system with TRV before. I designed this with help from many of you, so thanks


  • hot_rodhot_rod Member Posts: 13,323
    It’s a combi? If so it has a Circ inside. Primary secondary is what the manual recommends
    Full flow piping is an option in some cases where you can assure adequate flow
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • SnowmeltSnowmelt Member Posts: 1,192
    is that a aqua pure descaling filter or a sediment filter
  • GroundUpGroundUp Member Posts: 971
    He obviously did not read the manual. As mentioned above, the Noble has an onboard circ and needs to be P/S according to Lochinvar. I'd make him fix it. You'll have problems regardless of circ placement without P/S, as there may be instances where only one or two TRV are open which will not provide adequate flow through the boiler
  • hot_rodhot_rod Member Posts: 13,323
    With a pump in the boiler and if the other is in the supply I think you have two in series pumping at the expansion tank? Not the best piping if this is correct?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • OhioboilerOhioboiler Member Posts: 6
    Thanks for the reply’s. I am confused. I used the Caleffi Hydronics manual as the model for this, where they show a “home run” system. Although I’m sure most of you know this book backwards and forwards, I’ve included a screenshot for reference.

    The filter is from Caleffi. I am on a private well With hard water and thought it was worth a try.

    I’ve also included a pic of where they originally installed the pump. I thought pumping away was preferred.

    Can anyone point me to a better piping diagram?

    I have cast iron rads each with a TRV, Lochinvar combi unit (it does have an pump in the boiler), Alpha2 pump and manifold. Thank you

  • rick in Alaskarick in Alaska Member Posts: 1,082
    Unfortunately, you will need to re-do the piping. The picture in the Caleffi manual is for a boiler different then what you have, and can use that piping configuration. Your boiler can't. You need to pull out the manual for the Lochinvar boiler you have and pipe it the way they show it.
  • STEVEusaPASTEVEusaPA Member Posts: 4,143
    edited December 2019
    You can also install the manifolds upside down so all your loops can go into the top and you wouldn't need that big down and up loop into the manifolds for the tubing.
  • ZmanZman Member Posts: 5,831
    What model is it?
    Have you looked in the manual?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • hot_rodhot_rod Member Posts: 13,323
    The icon used in the schematics is also intended to indicate the type of boiler, the pic you show is a cast iron, low or no pressure drop boiler.

    Circulators should always have the motor horizontal.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • mikeg2015mikeg2015 Member Posts: 1,178

    Yup, circulator motor must be horizontal per the manual. You know, tat piece of paper most all contractors throw away because they know it all.

    I double check manuals all the time. Mostly because I’m newer, but also because i can’t remember everything. Taking 5 minute to read and 10 minutes to stop and think and discuss the plan, saves hours of re-work all the time. Just don’t tell my boss that.
  • OhioboilerOhioboiler Member Posts: 6
    edited December 2019
    Thank you for this help. Here is the piping diagram from The Lochinvar manual:

    First of all, do I need PRIMARY-SECONDAY PPIPING? I didn’t think it was necessary with a home run system. Am I wrong?

    Second issue is the pump placement. Original install

    I told them to move the pump to supply side, which they did:

    However, I thought the pump should be between the expansion tank and the manifold. Is this correct?

    This is the Noble Combi boiler (with onboard circulator) with Alpha2 pump, manifold and home runs to cast iron radiators each equipped with TRV.

    I will make the necessary corrections myself and have the installers do fill and start up.

    Also, I am so appreciative of this site. I went out of my way to purchase material from the advertisers from this site and Caleffi as a form of thank you

    rick in Alaska
  • DZoroDZoro Member Posts: 1,035
    Agree with all the above. On the domestic side you also need a T&P valve and a domestic mixing valve.
  • OhioboilerOhioboiler Member Posts: 6
    edited December 2019
    I asked the installer to move the pump and do p/s piping. This is what they did, but I still think it’s wrong:

    Shouldn’t there be closely spaced tee’s with the returned piped after the supply? Should I have them fix it again?

    I am out of town and only see photos of what they have done so if someone can point me to a piping diagram they can follow, it would be helpful
  • GroundUpGroundUp Member Posts: 971
    For cripes' sake, can these meatballs not read the manual?? Yes it's still wrong, need closely spaced tees or a hydrosep for p/s to work. They're closer now than before, but still pretty far from correct
  • JakeCKJakeCK Member Posts: 138
    edited December 2019
    Not only wrong but the solder joints look horrible, at least in the picture right by where they scorched the wood. Maybe its noise from the compression of the jpeg?
  • DZoroDZoro Member Posts: 1,035
    You posted the proper diagram from the manual!!!
    Can't they follow the fine picture?
    I see they push fit a mixing valve in, but still missing domestic pressure relief safety. Should also be service cleaning valve for annual cleaning of the plate heat exchanger.
    Hopefully you can get them to get it right.
    Good luck!
  • DZoroDZoro Member Posts: 1,035
    When they come back make sure to have them leave their combustion report print out inside the boiler. That way you know it was properly tuned to the proper specs. So you will have a proper set up, and the best performance possible, to have a nice long lasting system.
    Post the numbers here to confirm their results.
  • OhioboilerOhioboiler Member Posts: 6
    UPDATE. I finally returned home. The boiler and rads are working. They didn’t leave combustion reports, and they won’t provide them. The water temp leaving the boiler has never been above 110, so I’m thinking they didn’t run set up as well. I did the heat loss calculation with design day at zero. Am I able to go into the controls and change it from default (10). Here is the final install, not elegant but close enough for now. I needed heat for the wife and kids while I was away for work and these guys were all that was available. If I can get into the controls, any guidance and what setting to use?
  • Jamie HallJamie Hall Member Posts: 12,863
    If they didn't leave combustion reports, and won't provide them, I have to wonder if they actually did them. Cynic. Got another service company you can call? Where are you? Maybe we know someone.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • OhioboilerOhioboiler Member Posts: 6
    I’m as cynical as well and don’t believe they did them either. I’m in southern Ohio (Chillicothe).
  • bob eckbob eck Member Posts: 915
    We installed a Lochinvar Noble combi boiler in my father in laws house and when we set the programming it did not store it and we had to reprogram the boiler. Everything has been fine with the boiler since we did that. Installed the Noble combi boiler in October of 2017
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