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Vitodens 100

Tom Hopkins
Tom Hopkins Member Posts: 552
I have been reading through the Votodens 100 literature as I am about to install my first one. I have installed many of the 200 models with the sophisticated on board controls and and am trying to figure out the following:

Does the 100 output 1 single temp for DHW AND heating, requiring that it be mixed down for radiant floors, or are there 2) setpoints; 1 for Heating and 1 for DHW.

If the boiler is outputting 160°+ all the time it would not seem to be able to condense like a Vitodens 200 outputting 95°.

Are there 2 different tt connections like a Trinity, one for DHW and one for heating?

I cannot seem to find the answer in the literature.

Who has installed one of these in a combined installaion? Impressions?



  • Josh_10
    Josh_10 Member Posts: 787

    Nope.. One single temperature. It has an extra input for DHW but it doesn't have two temps. I understand that there is a remote 0-10V module you can install now to remotely modulate the boiler though.

    Also as I am sure you are aware from the 200's-- the venting is tough.
  • S.H
    S.H Member Posts: 1
    Vitodens help

    So Cal,
    Call me @ 1-877-853-3288 on Monday morning. This is the toll free number to Viessmann BC. I will explain how it works. Please ask for Stuart. Call after 8:30 am.
  • Leo G_101
    Leo G_101 Member Posts: 87

    there are 2 TT connections. One is for floor heating, with a reostat dial on the front panel, can set to temp. The other is for DHW/high temp. When closed, the boiler ignores the low temp tt, and fires up to about 176*.

    The wiring diagram should be attached to the inside of the cover. Very easy to read and wire.

    Instead of using a time delay relay, to purge the boiler after hi temp use, i used a Taco RMB.

    Leo G
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