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Viessmann oil fired boiler running real low wtr temp!

<strong>How is it possible I have an oil fired boiler running like a condensing boiler!!!</strong> Here is my story; I replaced my boiler with a Viessmann Vitorond and added the Vitotronic reset control on it. I had some trouble getting the control set up properly and the reset function working. After taking to the local rep I was put in touch with the guy at the factory who helped design the reset control for the boiler and set it up per his recommendations. But what I dont get is he had me set one of the dip switches for the min. water temp to 85 deg and not the 131 deg setting like i figured i would need, because it not a condensing boiler! The thing has been running for weeks now maintaining 115 deg on a 30 deg day heating the house just fine. I keep checking on the thing every couple of day and there is no water on the floor or anything dripping out around the flue piping. I asked someone else who has been installing Viessmann for a while and he said that the reset control is only made for that boiler, so if it has a setting for it, it must be ok and maybe because the flame is still the same temp all the time and doesnt modulate like a gas boiler that can turn it self down. Does anyone agree with this or do you think I have a disaster on my hand?
For what shall it profit a man, if he gains the whole world, and suffer the loss of his soul? Mark 8:36


  • STEVEusaPA
    STEVEusaPA Member Posts: 5,968
    The Viessmann....

    can run on water temps down to 80 degrees.  It doesnt mean you're not condensing, it just means the boiler can handle it.  Now your flue pipe, and chimney, I'm sure theyre condensing like crazy, and I think that will be a problem.  Did anyone check the temperature of the flue at the breech? What were the numbers?

    There is a Viessman guy on this site, and I'm sure when he sees your thread, he'll be able to help you further (his id might be ViessmanBob).
  • 300 deg

    300 deg
    For what shall it profit a man, if he gains the whole world, and suffer the loss of his soul? Mark 8:36
  • billtwocase
    billtwocase Member Posts: 2,385
    I'm confused

    You are talking water temps not breech stack temps right?  I think the water temps are a little low for 30 degree temp. Is there a stainless liner for the chimney? Was the stack temp checked?
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