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KN Boiler

Timco Member Posts: 3,039

I have 2 of these in now and they are fantastic.

Just a guy running some pipes.


  • Brian_56
    Brian_56 Member Posts: 7
    KN Boiler

    Does anyone have any experience or thoughts on the Hydrotherm KN Boiler?
  • lownox
    lownox Member Posts: 12

    I haven't installed any (as I am not an installer), but I was involved in the development. I guess I am biased, but I like the design. Working with Ken Cohen was fun.
  • Brad White_189
    Brad White_189 Member Posts: 16
    We specify KN's

    routinely. When they first came out, we had they typical reaction of "What? Condensing cast iron?"

    This was followed by a few test runs, field visits and meeting with Ken Cohen and others from Mestek itself.

    We came away convinced that they addressed the condensing issue (down-draft combustion gas flow to shed gross condensate), casting size and geometry to deter thermal shock and wall thickness to allow any sacrificial erosion to stay within ASME requirements after 30 years.

    The low gas pressure requirements are a bonus, especially here in Boston.

    As far as projects, I specified a KN10 in a school, a pair of KN6 in a retrofit for a concert hall, a KN6 for a student center and a pair of KN10's for a school to office conversion. All work fine but for the student center which is slated to go in soon. Taco also uses a pair of KN20's for their snow melt system.

    My $0.02

  • Brian_56
    Brian_56 Member Posts: 7

    Has there been any service issues or trouble with getting parts in a reasonable amount of time?
  • L'town radiant
    L'town radiant Member Posts: 36

    What would be thier advantage over a typical stainless steel or cast aluminum design condensing boiler?
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,090
    They have a banner

    on our High-Efficiency Systems page

    Pete Caruso is behind them.
    Retired and loving it.
  • Brad White_189
    Brad White_189 Member Posts: 16
    A slight

    cost advantage and the ability to operate on very low gas pressures come to mind. Simple hook-up. Parts are "off the shelf" Honeywell for example and our local vendor stocks a few, at least in the KN6 size. Small footprint and the ability to go to 180 or even 200 degrees if you need to retrofit into an older system. (Yes, you can do this and still enjoy condensing efficiency at least 70% of the season.)

    It is good in competitive public bidding to have choices and this is a welcome addition.
    Nothing wrong with the others in principle- this is another way to serve the market.
  • Brad White_189
    Brad White_189 Member Posts: 16

    No strong issues I know of; on one job the control boards had to be replaced at least once, maybe twice, but the local rep and Mestek were on the case as fast as I have seen, in the field. Boilers finished their first season without complaint. The other systems have gone through one and two seasons without a ripple; I would have heard otherwise and indeed, I do ask.
This discussion has been closed.