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Viessmann: Vitotrol 200 or 300 controller -- or none. Help!

TAG
TAG Member Posts: 488
Viessmann 200 -19 boiler w/ indirect.

How do most people set these up -- with control? If so .. 200 or 300? The boiler is providing radiant and DHW -- I'm not using the second heat curve.

I do understand that I do not have to use a controller. It looks like the 300 has a digital display and I see it has the capacity to adjust the second curve on the boiler (that I am not using). I'm trying to understand what it does and what the display shows .... can I program the boiler with the 300 ? I'm assuming with the 200 not having a display -- it's not able to do much?

I'm familiar with the old Buderus logmatic/ eccomatic controls -- they had a BFM room thermostat/controller that acted as an override. If you were cold -- moving the BFM could adjust the curve. It was like a fine tune of the boilers reset. The BFM also had a setback value if you had that activated. That's all it did -- was only marginally useful. You could also turn off the boiler's heat if my memory is correct. It was overpriced .. like the Viessmann 200/300 .. that sort of match the model number in dollar bill cost.

Thanks

Comments

  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 2,784
    edited August 2020
    Yes, just as you said. The 200 is like a regular, everyday thermostat while the 300 gives you access to all the parameters available on the Vitotronic control at the boiler. 

    I’d say the 300 control is not for the everyday homeowner, but for the technical person that wants more hands-on access without having to visit the boiler room. 
    Often wrong, never in doubt.
  • TAG
    TAG Member Posts: 488
    Thanks -- have received conflicting information Some strident w/o real knowledge I come to find. Know there are some here who do many Viessmann installs.

    My project has encountered delay after delay. Insurance / Township/ Fired builder. Every set of eyes want to go a different direction. I ended up with a lot of uninstalled parts that I can't afford to just toss and start over. The current HVAC people have been doing a fantastic job .... But -- no great Viessmann knowledge.

    If there is any real benefit to the controller for the $100 extra the 300 may be the ticket
  • Paul Pollets
    Paul Pollets Member Posts: 3,393
    If you were using 2 circuits with a mixing valve, the Vitotrol 200 could act as a sensor for each zone. It's programmable, Each circuit can handle either thermostat. Like Alan said, the 300 is for more tech oriented owners. Both have the same internal sensor. The main reason for the Vitotrols' is they allow continuous circulation with variable temperature within the circuit, and don't stop the flow, unlike zone valves or pumps on a thermostat and relay.
  • TAG
    TAG Member Posts: 488
    edited August 2020
    Oh -- so you can have a 200 or 300 on each heating curve. I guess that's how the Buderus worked as well and it makes perfect sense.

    While my project has three radiant types: Warmboard/ underfloor plates/ slab .... it looks like my water temp is about the same.
  • Paul Pollets
    Paul Pollets Member Posts: 3,393
    the only way to tell is run a software program and check. (Uponor ADS is a good one) Typically slab radiant is 30-40 degrees less than staple-up with plates. The rule calls for a different circuit temp if the application has more than a 10 degree difference.
  • TAG
    TAG Member Posts: 488
    I'm using the heavy plates and the manufacturer is telling me that I'm at about the same temp water for the needed output as the Warmboard.

    The slabs ( 8 loops) my plan was thermostats on the manifold -- two spaces one with no windows .. the other has a bunch. That one about matched the warmboard
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 2,784
    edited August 2020
    Smart to zone the rooms separately seeing that they have different amounts of glazing. Smart again to use the thicker accelerator plates  Far be it from me why people go cheap. 

    You will love your Viessmann boiler. 
    Often wrong, never in doubt.
  • TAG
    TAG Member Posts: 488
    Paul -- We did do the numbers. The problem is the project is a converted church and with everything being open to each other it's tricky.

    The most exposed area (lost of windows) is one of the slabs - about 500sf. The other slab .. also about 500 feet is on the interior and will need much less. The Warmboard is coming in with water temps on the low side.

    Even if I tried to have a second water temp -- one for the slab .. it would not work for both.

    I have used a floor thermostat -- but it was a long time ago and I can't remember who made it
  • Paul Pollets
    Paul Pollets Member Posts: 3,393
    Balancing the manifolds without a chart takes lots of time. Some put a telestat on every port and leave the flow wide open. The Vitotrol will help, but won't assure that each loop is balanced. Setting the correct heating curve will be a little trial and error.
  • TAG
    TAG Member Posts: 488
    Paul: I'm not sure what you speak when you say "balancing the manifolds". Each one or with-in each manifold?

    I have always found these systems to be a bit of "trial and error" to get them set up.

    Warmboard did a great job of zoning the project and matching the loop lengths -- I have to use some controls on the loops. My plan was to go with the Cross with those -- by the time you buy all the telstats and the manifold -- it's sort of a wash (it seems)
  • Paul Pollets
    Paul Pollets Member Posts: 3,393
    Each manifold port has a balancing screw or cap. Turning it determines the flow rate of the loop attached. It's possible to determine the correct flow rate manually...I'd refer to Uponor's CDAM. It presumes the right target temperature for the manifold is accurate. If the design is done with the software, and you have a modulating boiler on outdoor reset, no telestats are needed and the ambient temps should be the same, if the manifolds are balanced. Most owner's want a thermostat in the bedroom(s) and that is easy to add.
  • TAG
    TAG Member Posts: 488
    Paul - assumed that's what you were talking about. My first project back in the early 90's was a difficult retrofit w/ differing loop lengths -- even with the visible flow gauges on each loop it took some playing around to get the radiant dialed in.

    Since this is a stone church -- each room has various sun gain as it goes around the building. It high VS wide .. so thermostats will be part of the mix.

    My goal is to keep is simple .. or as simple as logical.
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