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Viessmann 100, 200, or Bosch?

Were replacing a 7 year old boiler nightmare, (HTP Munchkin MC-120 which is 120000 btu ). Our requirements are 1450 sq-ft house with air handler, indirect water heater, and 1000 sq-ft attached garage with floor heat. The present munchkin is installed in the crawl space with a space from cement cap to the floor above of 68 inches, this is between the floor joyces that are about 24 inches apart.. My question is how much room is required for a Bosch, and for a Viessmann. and is the Viessmann 100 capable of servicing my 3 heating requirements or do I need a Viessmann200. I will also add that my previous plumber 7 years ago added some black pipe to make a circle with a pump, a air handler that also has another pump, floor heat with another pump, the garage floor heat also has a mixing valve and another pump, indirect water heater with another water pump, with relay switches and water heater had priority. So before I start to contact plumbers to try and get an estimate if any will even commit to redo's now a days, WHAT IS THE BEST OPTION between these 3 boilers, or who makes the best?

Comments

  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    You need to do/have a heatloss calculation in order to size a boiler properly. I'm gonna take a stab that a 120,000 btu boiler is at least double what you would need.

    A Viessmann 100 vs 200 is really better controls and a better turndown ratio with is beneficial. The "loop" you refer to is likely a primary/secondary setup. Post some pictures of all the piping for a distance where we can see what's going on.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
    knotgrumpy
  • Tinman
    Tinman Member Posts: 2,808
    Viessmann Vitocrossal CU3A. I love Lochinvar but this is the best boiler on the planet in my sometimes not so humble opinion.
    Steve Minnich
    SuperJShahrdad
  • Eastman
    Eastman Member Posts: 927
    What is notable about the Vitocrossal CU3A?
  • aceallenk
    aceallenk Member Posts: 2
    Thank for reply Solid Fuel. i'm going to assume 120000 btu is correct and previous plumber did his homework in that department as temperature here in Saskatchewan Canada can dip below the -40 C/F and colder plus wind chills. I'll be getting that double checked by who ever I decide in the end to replace the new boiler with, and I think my air handler is rated for that size. I guess my question would be better asked this way between the Viessmann 100 and 200 which is better quality/cost/reviews/warranty providing a person don't need the bells and whistles, then compare that to a Bosch for basically the same reasons. What i'm hoping is to find a top brand from people experience, rather than high priced advertising reviews. We all know everything breaks and can get a few poor reviews, as well as poor installation can add to some low reviews and some poor ratings. Example my Munchkin probably has 3000 poor reviews compared to a Viessmann with 18. So what I'm trying to determine is which brand is the top brand, and I have a wall basically 68 inches high to mount to. Maybe I shouldn't even be wasting my time reviewing a Viessman or Bosch, perhaps there are better condensing boilers available. From my 1/2 day of reading etc these 2 boilers kinda seem to have a fairly good rep, and trying to remain open minded I have a thumb up for Bosch from several other uses from windshield whippers to oil filters. They do seem to make good products, just know nothing of there boilers, or do I even have the room to install one..
  • lchmb
    lchmb Member Posts: 2,997
    I've installed a number of Bosch, as well as Viessmann. I like them both. I also like the GV-90 from Weil Mclain.. biggest issue is what the installer likes to work on, and who has parts available.. best equipment in the world can break... at -40 I'd want to be able to fix it quick..
    STEVEusaPADZoro
  • Tinman
    Tinman Member Posts: 2,808
    @Eastman - Bullet proof HX, water content extremely high, built to last like no other mod con I’ve put hands on. You’ll never need a buffer tank or have to worry about short cycling because of the water capacity. Proven control.
    Steve Minnich
  • Eastman
    Eastman Member Posts: 927
    That looks nice.
  • NY_Rob
    NY_Rob Member Posts: 1,370
    edited December 2018
    aceallenk said:

    i'm going to assume 120000 btu is correct and previous plumber did his homework in that department as temperature here in Saskatchewan Canada can dip below the -40 C/F and colder plus wind chills.

    FWIW- the "average" heatloss for a post WW2 2x4 construction home in the US is 15-20BTU's per sq/ft.
    Yes, you're in Canada... but you are indicating a 49 BTU per sq/ft heatloss in your house/garage! You do close your windows during the winter don't you? ;) If you remove the garage from the equation, the heatloss from the the 1450 sq-ft house is probably not more that 30K BTU's.

    I'm guessing your previous plumber did not perform a heatloss analysis and simply replaced your boiler by looking at the rating plate on the old boiler which has left you with a seriously oversized boiler.

    Slant fin has a free heat loss app that consumers can use to estimate their heatloss.... give it a try:

    https://www.slantfin.com/slantfin-heat-loss-calculator/
    Solid_Fuel_ManZman
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,979
    edited December 2018
    I like Viessmann as well and is my go-to boiler. No experience with Bosch.
    However, I service many Munchkins here in the Bay Area and as they are starting to fail, I've been using IBC boilers as replacements, specifically their SL Series G3:

    http://www.usa.ibcboiler.com/ibc-products/sl-series-g3/

    I especially like their side connections - you can choose left or right - and they have a very easy to use user interface. AND they are made in Canada!

    Their SL 14-115G3 would be the right size for you:

    http://www.ibcboiler.com/wp-content/themes/ibc/pdf/SL-14-115-G3-Sales.pdf
    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
    kcopp
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    There are a lot of Bosch boilers around here. The cast aluminum Heat Exchanger is what steers me clear of installing them. I'd go with the CU3A if you can afford it!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Tinman
    Tinman Member Posts: 2,808
    Everyone should check with their supply houses. V’s numbers iare more competitive than ever with the other big players now.
    Steve Minnich
  • gennady
    gennady Member Posts: 839
    I love viessmann. I would not use cu3a if there tight space or stairs. Heavy and large to move around. Also it still needs P/S if you want presize system temperature control, despite being designed for direct piping.
    For different temp zones you will need viessmann mixing valve if you want properly designed system.
    200 is the best bang for the buck. 100 is stripped version of 200, without combustion control, mixing valve connection option and limited outdoor reset and no programming. I installed few 100, it cost me more to implement full system than if I would install 200. So I stopped offering 100.
  • Eastman
    Eastman Member Posts: 927
    Does Viessmann have an indoor feedback system available?
  • gennady
    gennady Member Posts: 839
    edited December 2018
    There is.
  • Tinman
    Tinman Member Posts: 2,808
    It’s as big as a refrigerator but lighter than a cast iron boiler.
    Steve Minnich
  • HEATthis08
    HEATthis08 Member Posts: 4
    Veissmann is there any other boiler,I think not!!!
    Solid_Fuel_ManPaul Pollets
  • tim smith
    tim smith Member Posts: 2,752
    Why is Lochinvar not in discussion, the khb (floor mount) or the WHB (wall mount). Both 10:1, the knight fire tube has been bullet proof for me over last 7 yrs. yes if multi zone you will pipe pri/sec but not big deal. Viessmann is good boiler but.....,definitely not a hands down choice.
    Solid_Fuel_Man
  • Le John
    Le John Member Posts: 226
    @Steve Minnich Wow that is a big boiler!
  • GW
    GW Member Posts: 4,691
    Eastman said:

    Does Viessmann have an indoor feedback system available?

    we had to do somersaults to get a cu3a to work with a Vitotrol 200A. The customer is finally happy
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,979
    edited December 2018
    GW said:

    Eastman said:

    Does Viessmann have an indoor feedback system available?

    we had to do somersaults to get a cu3a to work with a Vitotrol 200A. The customer is finally happy
    What problems did you have? Were they learning curve problems or Viessmann problems that they had to correct? Viessmann culture can be counterintuitive.

    I believe Paul Pollets sets up a lot of his Viessmann systems with indoor and outdoor reset. Maybe he'll pipe up here.

    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
  • GW
    GW Member Posts: 4,691
    It was just settings. It just took about 5 phone calls to get it figured out.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    I usually set up the boilers with a Vitotrol 200A or 300A. Never with a regular thermostat. The Viessmann stats can be enabled or disabled as to indoor feedback, or usually set up for either the HC1 or HC2 zone. (but not both)
  • I usually set up the boilers with a Vitotrol 200A or 300A. Never with a regular thermostat. The Viessmann stats can be enabled or disabled as to indoor feedback, or usually set up for either the HC1 or HC2 zone. (but not both)

    HC1 or HC2: Are these for different temperatures?

    So, these are constant circulation heating systems working on outdoor reset, correct? I have a hard time getting customers to accept heating without thermostats.
    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
  • GW
    GW Member Posts: 4,691
    Alan that's fine but the boiler will sit there and make heat when no zones are calling, so just get ready for that question.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,979
    edited December 2018
    Yeah, that happens and the LLH gets hot, but it goes no further if there's no call for heat from the thermostats. I explain that to my customers and it's never been a problem. If I didn't explain it, they'd be calling me I'm sure.
    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
  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    HC1 is the high temp circuit and HC2 is the mixing valve, if installed. The boiler computer recognizes when the mixed temp is present and allows 2 heating curves to be programmed
  • sallaberry
    sallaberry Member Posts: 19
    Why not the 222 it would get rid of the indirect water heater and still have all the features of a 200. 100 would be too small if the heat calcs were done correctly.