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Viesmann headaches

CBRob Member Posts: 273
I'm working with my boiler guy to repair a 15 year old viesmann vitoden 200.

Its been one thing after another..
Its a custom home and the original owners went overboard with viesmann components.
Side by side boilers, Vitocontrol. Mixing valve. and a few other components to boot.
We have been replacing parts frequently and at great expense.
Circ pump, fan, control input, control board and a few other things.

Parts are fricken expensive and local labor is also sky high.
No real viesmann experts in the state either.
I'm inclined to suggest to the owners that it may be time to retire the viesmann boilers and switch to triangle tube or similar.
I am the property manager and am overwhelmed with most of the problems that come up with the boilers .
I can make simple fixes and trouble shoot other boilers.

Anyone been in this situation?
Is frustration with viesmann common elsewhere? None of my local boiler guys even want to work on them.


  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    If the techs took the training offered by Viessmann, they would feel comfortable working on the machines. Without training, it becomes difficult and not a lot of techs today like attending classes, or reading the manuals.
  • psb75
    psb75 Member Posts: 804
    I believe they are the most sold boilers in the world. They don't have a large footprint in the USA, esp. in some states.
  • Moose907
    Moose907 Member Posts: 2
    We are in Alaska and bought a house with a Viessmann. Same story, contractors don’t want to touch them only because they don’t have experience with Viessmann. From what I understand, Viessmann are more east coast in North America. I found a top notch contractor and between him and the Viessmann Technical Support (phone), we got it licked. Yes parts are crazy. $1K+ for the Viessmann pump relay control. I shadowed my contractor the entire time and gained a lot of clarity in the system and how it works. I went through coding and researched what I didn’t understand. Runs better than ever now. I also watched the Viessmann training videos on maintenance and will be doing that myself now. My takeaway about Viessmann is that they are a very customizable boiler (coding) and work very well when set up correctly.
  • psb75
    psb75 Member Posts: 804
    Viessmann boilers are very nice machines. The company is top notch. I dealt with "voluntary recall" replacement of heat exchangers on a floor-standing mod con combi model of theirs this year. They provided the new heat-x's, plus other stuff, AND paid for labor and travel. Their equipment is designed with the service person in mind--is my impression after this experience.
    The co. struggles with their "presence" in U.S. market. It has a higher price point.
    For sure, "familiarity with your product" is key in the heating service industry. Study your Viessmann manual. Its time well spent.
  • Zman
    Zman Member Posts: 7,542
    Viessmann controls are counterintuitive to many, including myself. They have lost a good deal of market share in Colorado in the last few years. You might try reaching out to the distributor McNevin Company - 303-322-0165 to try to find trained techs or get some training yourself.

    It does not sound like they are popular in your area but Lochinvar has dominated my market area for the last 5 years. Shamrock Sales in Denver offers fantastic support locally and their national tech support will pick up on Sundays.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • CBRob
    CBRob Member Posts: 273
    Thank you for the feedback guys.
    There are only a few viesmann boilers around here and I don't think my heating guys feel it worth the time to take courses.

    We are waiting for a circuit board to show up now, hopefully that has it operating again.

    My experience with the snowmelt system I just installed has helped me learn a ton about condensing boilers
    I think the side by side viesmann setup has been set wrong from the get go.

    I need to learn the setup myself and reprogram

    Its been running way hotter than needed, and I think it's even set above condensing temps and then cooled down by mixing valve.

    Lots of resources out there for new viesmann stuff. This is s wb2a from around 2006.
    Has a programmable mixing valve too.
    Big control on it, and screen.

    More research...
  • psb75
    psb75 Member Posts: 804
    Viessmann boilers have a whole lot of inherent "power in design" and their features frequently aren't understood or even utilized. What is also elegant about their design is that I can tell that thought was given to the SERVICE PERSON. (Hmmmm? I wonder if they intuited that I, as an installer sometimes "wear the hat" of a SALES person?) All I'm saying is: don't blame Viessmann.
  • rwhtg
    rwhtg Member Posts: 34
    Where are you located? Any system pics? The viessmann web site offers great information on current and “ historic” products. Just about any and all literature you could need is there.


    You can also located a qualified contractor in your area there as well. Partners are good, pro contractors are great.

    Skilled labor isn’t cheap, cheap labor isn’t skilled.
  • CBRob
    CBRob Member Posts: 273
    I'll get some pics today.
    I'm in the middle of Colorado at Crested Butte Ski area.
    Thanks for the links.
    I've been looking for info on the smart mixing valve we have.

    Its crazy just how much stuff they have crammed into a small boiler room.
  • CBRob
    CBRob Member Posts: 273
    I'm pretty sure I need to adjust something between the Vito control and the boiler.
    Even with an outside temp of 40 degrees I have supply temps at 160 from the boiler and supply temps of 120 after the mixing valve.
    Seems like the boiler should just put out 120, or even less.

    The ch limit on the boiler was set at 204f

    Which also seems crazy high.
  • HomerJSmith
    HomerJSmith Member Posts: 2,388
    edited November 2019
    The trouble with Viessmann is they are German and the Germans over engineer everything. Like all things, understanding the unit makes repairs easy but expensive.
  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    edited November 2019
    The HK-1 on the mixing valve controls the mix temperature only and has it's own heating curve. The Tekmar OR control probably handles the boiler temperature. Since I can't see the boiler, or near boiler piping...
  • Simply Rad_2
    Simply Rad_2 Member Posts: 171
    CB Rob

    There are plenty of qualified Viessmann installers in Colorado. The Viessmann western Rep also lives in CB
    Carrie Betz (970) 596-8430
  • CBRob
    CBRob Member Posts: 273
    edited November 2019
    I had heard rumor that there was a viessman higher up here from the guys at Ferguson.
    Didn't know who.

    I have been studying all the manuals that came with it, it fills up a binder.
    I've got a decent grasp on the fundamentals now.
    I'll reach out to Carrie.
    This made my day.
  • Viessmann is top shelf; tech. support is fantastic.

    Fifteen years in Crested Butte with snow melt may be nearing the end of the boiler's life. I'd be checking and cleaning the Giannoni heat exchanger yearly.

    Wonderful town; great mountain biking. Apologies that Fairfax, CA took away the Mountain Bike Hall of Fame since we invented the sport. : )
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • CBRob
    CBRob Member Posts: 273
    edited November 2019
    That is funny about the mountain bikes. Some of the old timers here really think they invented the sport.

    Yep about the 15-year mark on the viessmans.
    I don't think the heat exchangers ever been cleaned.

    it's kind of a shame but I don't think it was ever really set up right to begin with. I think it's always ran too hot, the primary loop seem like it was always running and always really hot. Like it didn't even have a warm weather cut off.
  • CBRob
    CBRob Member Posts: 273
    I spoke with the Colorado rep today.
    Carrie is going to stop by my job next week!
    Stoked to get a Viessmann lesson from a pro.
    She's super nice too.
    SeanBeansAlan (California Radiant) Forbes
  • Good contact resource from Jeffrey!
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • Simply Rad
    Simply Rad Member Posts: 183
    CB Rob
    Glad to help
    I am in Steamboat, alittle far away to help. What are you and Alan doing up at 1:15 am on heating help
    Jeffrey Campbell
    Alan (California Radiant) Forbes
  • CBRob
    CBRob Member Posts: 273
    > @Simply Rad said:
    > CB Rob
    > Glad to help
    > I am in Steamboat, alittle far away to help. What are you and Alan doing up at 1:15 am on heating help

    Enjoying a good book and too much coffee