Control options with Vitodens 200 WB2B (Vitotronic 200 + Vitotrol 300)

smihaila

But doesn't that create a contradiction

of terms, when you say "Having variable speed on both sides gives you that advantage and in all actuality eliminates the need for pri/sec piping or as I call it, boiler protection for a mod/con."



How can you have var speed on both sides without having a pri/sec piping?

Do you see the conflict? :-)

Or you mean "sides" in a diffent sense. Guys, I cannot follow you anymore :-)

Too much hermeneutics. Why are you afraid that the enlightment will get to too many folks? The enlightment is always beautiful and truth is always good for everybody.

CMadatMe

I'm sorry

Let me clarify. You wouldn't need 2 pumps nor pri/sec unless the pump could not overcome the pressure drop of the boiler and system at design flow rate or your low end flow rate is too small.



The boiler will modulate based off the temp rise. Yes folks that's what speeds and slows fan speed. ODR is a temp target. Temp Rise is the aiming device the control logic uses to achieve the temp target.

smihaila

Now you are coming home

Very well said and clear now. Yes, indeed, this makes perfect sense.

Thank you Chris!

smihaila

Long time no see

Hi everyone,

We have just finished our DYI hydronic project around August this year. Now I finally have a bit of time to report back with results. I have posted some pictures into a new thread, if you are interested. Wished to post even more pictures with the rads and piping through the house, but there is some limit in how many pictures can be posted I guess.

Thank you all for helping us with this project, especially to Chris, who had the inspired idea of suggesting us the Lochinvar. It proved to be an excellent choice. Thank you Chris!