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Vitodens 200 Lamda Pro

ERF Member Posts: 51

How would a Viessmann vitodens 200 lamda Pro fit into

a situation like this?

!. Basement Bed & Bathroom with fin-tube BB on own T-stat

2. !st FL, Kitchen & Bathroom recessed rads. Living & Dining Room,

free standing rads, on own T-stat.

3. Up-stairs apt. Kitchen, Living, Bedroom & Bath loop of fin-tube BB on own T-stat.</span>


  • Radman
    Radman Member Posts: 70
    Switch to TRVs...

    Hi ERF,

    You will first want to perform a load calculation to size the system properly.  If each zone is capable of delivering heat at water temperatures below 162deg F then you will like your Vitodens.  The EDR for the recessed radiators will need to be calc'd along with the freestanding rads.  You will find the system will perform best under continuous circulation on the system side.  Retrofitting thermostatic radiator valves on those zones will increase comfort and even out any temperature swings.  If the piping on the radiators is a series loop, then you might consider piping them parallel so you can zone each rad.  If not, a remote TRV will work.   I have put a lot of Vitodens in, and it is our primary boiler.  I have one in my house connected to crappy old baseboard (I am due to change it out) but since installing the TRVs on each zone the house has never felt better.   Our gas consumption is down about 35%, and last winter was cold for us here in CO.  Typically baseboard systems are designed around about a 170 deg F avg water temp, but even when it is more than -10, we are heating the house comfortably with 159 deg F water. Again, careful sizing and system evaluation is key no matter what you install.
    "If it was easy, they would have called it PV."
  • binskibok
    binskibok Member Posts: 19
    BTU calc for convectors

    I'm looking @ the Vitodens 200 for a retrofit . How do I calculate Btu's for the existing convectors on the first floor    Living room 240sf   2 convectors  Length  44.5" depth 4.5" height 20" dining room 115 sf  one convector length 48.5"  bath 55sf  one convector 28.5"  and bedroom one convector 56.5".    Theses are not cast iron but black pipe to copper fin. New England cape built in the 50's.   
  • Gordan
    Gordan Member Posts: 891
    Might be of help

    I'm a homeowner, not a pro. I had a similar query a few months ago, and was pointed at the Beacon Morris web page for some output charts for the convectors. You can calculate your output based on the various dimensions of the heating element, but be sure to take into account all of the derating factors such as grille openings and height and depth of enclosure.

    That being said, that's not the way to determine what your heat loss is. But it could, once you know what your heat loss is, help you figure out whether it makes sense to pair a mod-con with these convectors. (They may - or may not - require supply water temperatures that are too high for any condensing to occur, thereby negating some of the value of a mod-con.)
  • ERF
    ERF Member Posts: 51

    Radman I agree that TRVs are the way to go.  The BBs in the system are easy to retrofit.  The CI built in convectors and free standing rads are on a mono-flow system and the piping is buried in the finished ceiling down stairs.  It would require a lot of demolition to access the pipes.  My own house has TRVs on all the BBs with constant circulation and is extremely comfortable.  I could run my system at 140 or less on the coldest day of the year and maintain 74*F with out breaking a sweat.  Thanks for the reply, Ernie    
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