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Quantum 95 vs WeilMclain Ultra

But even a modulating boiler should be sized properly. Most homes have design heat loads far less than the minimum modulation of the Q95.


  • John P
    John P Member Posts: 16

    Contractor proposing the Dunkirk Quantum 95 or WM Ultra for in floor and indirect water heater with superstor ultra tank. I would highly appreciate input from the crowd in regards to first hand issues with these products. I had heard that earlier Dunkirk models had some issues. Thank you very much
  • ALH_4
    ALH_4 Member Posts: 1,790

    The biggest concern I would have with the Q95 is that it's only available in an 80-200MBH size. Does that match your heat load?
  • Empire_2
    Empire_2 Member Posts: 2,343
    Hey Guy's

    The Q95 is a full modulating boiler and can meet demands from 75M to 200m. Also equipped with the ORC for additional fuel savings. I like them since they do not need the Primary secondary loop. BUT,... I pipe it this way to provide total comfort. I will try to forward specs on this model...

    Mike T.
  • Bob Gagnon plumbing and heating
    UB95M-200 Dunkirk/ Utica

    I vote for Utica's UB95M-200. Utica's service, and commitment to building a quality boiler is hard to match. I am installing my third one now. I haven't heard of any problems, they have been available in my area for only a year or so now. You have to set gas pressure and do a combustion test with this boiler. Thanks, Bob Gagnon

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  • Glenn Sossin_2
    Glenn Sossin_2 Member Posts: 592
    Dunkirk / Utica my vote

    If your mounting up against a wall, you don't want the Ultra. The wiring terminal strip is located in the back behind the vent pipes - virtually impossible to access without disconnecting the vent and intake piping.

    The Ultra is also requires primary / secondary piping. There is a high head loss through the exchanger. The Dunkirk/Utica is relatively low head loss.

    Both boilers use the same MCBA logic board. My opinion, the Dunkirk/Utica is designed much better.
  • Tom Hopkins
    Tom Hopkins Member Posts: 554
    Prestige is MBCA controlled

    Triangle-Tube's wall hung SS low-head self-cleaning HX boiler can be piped direct instead of primary secondary for greater ΔT and lower kWh consumption, not require any chemical balancing unless the water actually needs it, and use the same MCBA controller. It's not prone to short cycle because of how the controller is configured by T-T to handle the firing cycles and how it monitors ΔTs. The Prestige fires for 10 minutes at a time (unless the ΔT rises too fast or that it's going to meet target temp) rather than split a 10 minute combined on/off period like the Ultra, although I'm not sure how the new Ultra will handle "this", nor the ECR - fewer but longer firings. This being how to operate so that the on/off cycles are optimized to meet certain preferences when outdoor temperatures are above the point where the boiler can't run at minimum modulate continuously without overheating the house.

    Once boilers have to satisfy these lower loads they switch to some form of pulse and glide like hypermilers do with their cars to exceed 100mpg, and they achieve great savings in these low ranges compared to the bang bang boilers which simply get too hot each cycle or mess up their flue. Many if not most m-c boilers spend the vast majority of their lives at outdoor temperatures above their minimum modulation and that is where the Prestige is a boiler that really merits consideration.

    I hate to be an Alu basher but I'd feel much better knowing my heat exchanger was made from a universally recognized top grade material for this application - that being 439 SS. As for raw heat transfer Alu certainly has an advantage in the acceleration of the ΔT of the HX in both directions. However, with the savings for any of these boilers leaving so little room for improvement in fuel savings, the difference simply can't be enough for me (is is $5/yr, 1, I doubt $20 or even 10 for a normal house) to consider anything less than top grade SS.

    The lifespan may not matter if these units all get too expensive to maintain after 10 to 15 years which Alu should easily go, but if the controllers and parts can go 25 years at minimal costs, then the Perstige's 439 HX would be my prediction of a material and design that can go the distance.
  • Floyd
    Floyd Member Posts: 429
    Hello here....!!!!!

    Andrew has a valid point here and everyone of the other posts have failed to address the MOST important issue when looking at a boiler install... SIZING!!!! Installing an oversized boiler is a bit like the 1832cc engine in my Goldwing, nice to have the power, but never will use it all, and eff. is not what it would be if you matched power available with power needed.
    Then the question is, why install a "high eff." boiler and then kill the eff. with a mismatch of power??? The Dunkirk is not a bad boiler, but the ability to match the boiler with normal residential loads simply is not there....
    Make sure that the contractor does a realistic heat loss... THEN, match a boiler to that...the Ultra will match up much better and desipte a few inconvenient things like the terminal strip it is a very good boiler also...a little fore thought can easily overcome that.
    Why on earth would you take a new fangled Mod-Con and turn it into an old fashioned bang-bang????

  • Mitch_4
    Mitch_4 Member Posts: 955
    The Dunkirk

    While Stainless seems to get the best hurrah, most warranties are 10 year. The Dunkirk is 10 year non prorated, and an additional 5 years prorated after that for 15 year total

    "I hate to be an Alu basher but I'd feel much better knowing my heat exchanger was made from a universally recognized top grade material for this application - that being 439 SS"

    Aluminium is 5x better at heat transfer that SS and 3x better than CI, and if "top grade" is SS why the shorter warranty? (sounds like you work there :-), which is fine..) Aluminum has many historic applications as well, cola cans (is anything more corrosive?) and engine blocks (now there is thermal punishment)

    The Dunkirk line has been using Cast Alum for about 15 years, myself going on 5 years with the product..easy install and ZERO issues. No pri / sec for the dunkirk and if you look at the banner above, free 5 year parts and LABOUR warranty if installed by a dealer.

    I have been using ECR product in Canada (under the Olsen name) for years, and have yet to be dissapointed.
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