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Cold Start boilers piped in Series?

Wynston Member Posts: 3
I was asked by a local church to stop in and have a looked at their boilers as they do not seem to be working properly. I believe there is some wiring issues, but I believe there are piping issues as well. They are two Viesmann Oil Fired Cold start boilers(which I haven't worked with before but have plenty of experience with Buderus and Weil-McLain), the funny things is though is they are piped in series, instead of parallel, or as I prefer in a true primary/secondary fashion. I have never seen two boilers in series before(other than in some instances of wood boilers tied into oil boilers, and I have been at plumbing/fitting for 10ish years now), is there a reason why the installer maybe piped it in this fashion that you could think of? I have done some web searching and can't see any one recommending installing these boilers this way. All this money they spent on fancy controls, that I think would be so much better suited to a primary/secondary arrangement. I don't want to start trying to convince them to let me re-pipe it if there may be a reason for this arrangement..... Thanks for your replies, I can provide more info if needed


  • icesailor
    icesailor Member Posts: 7,265
    A boiler install is only as good as the installer. There must be some issue or else, why did they call you?
  • Rich_49
    Rich_49 Member Posts: 2,766
    If possible I would love to see a picture of this . You should always have a camera for the odd occasion when you see a Bigfoot .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • RobG
    RobG Member Posts: 1,850
    Agree, photos are needed. A camera is one of the most valuable tools in your arsenal. I used to carry one before the digital days.
  • Wynston
    Wynston Member Posts: 3
    I will definitely snap a few photos, I didn't have my good phone on me, only my work assigned tough as nails, but old style flip phone, I would be better of drawing pictures they taking them with that. I do know I would want to see pics if I was reading this, so I promise I will get some up in the next few days.

    I was called for no other reason than a family member looks after maintenance for the church now, and more or less just want me to have a look and see what I thought. He noticed things were "weird" this past summer when he decided to shut things down for the summer months by turning off the emergency switch (yes, that is right, one switch for two separate boilers) And one boiler would immediately fire(no call for heat and no DHW) and the other would in fact power off. There is major electrical/control issues here as well that are going to need to be looked at as well.

    The boilers have been installed for 5+ years and are some how working enough to kind of heat the church (original part is 45-50years old, with a fair size addition done about 10 years ago.

    I am not really in a position to do any work, don't want to step on my companies toes. Being a fairly large commercial/industrial unionized plumbing/heating/welding company I am sure any price they would provide would be out of their budget, which is too bad because they need someone in there who takes pride in their work.

    Sorry for rambling on, based on the requests for pictures I can see that boilers piped in series are not just a mystery to me! :) I will get some pictures up. I will even snap some pictures of the breeching which is done in hardware store grade galvanized ductwork :) One last thing to add, in my small little province there is absolutely no heating codes of any type enforced for low pressure commercial setups, other than once a year a provincial inspector will come out and make sure your LWCO is working and to make sure someone didn't stick a cap/plug somewhere on the relief valve, or undersize it while replacing it