vitodens 200 additional circulator

gobucks823

I'm adding an additional zone (will be zone 2) to my Vitodens. Does the second zone circulator get wired to output 157? I'm not finding in the manual and I could've sworn there are connections for 2 zone circulators on the boiler. Am I wrong?

HVACNUT

The Vitodens 200 has only one zone dedicated to space heating. The boiler is designed to work without a thermostat and maintain room temp through constant circulation.
You need to add a 2 zone switching relay. I've seen it done but dont know exactly how. The application I saw had 2 hydro air zones, 3 radiant zones, and an indirect. I dont think it's as simple as connecting the relays dry contacts to taps 1-2 on the 143 external block. Maybe others here more experienced with Viessmann can help. Coding addresses will also need to be reprogrammed I believe.

gobucks823

Ok. That is making some sense then for why every piping description in the manual with more than 1 zone shows the second zone with a mixing valve.

gobucks823

I'll pick up a 3 zone pump switch on Monday. I was planning on not using thermostats and allowing the constant circulation of the zone pumps. Do I just jumper the stat connections on the switch together? I assume I remove my existing single zone pump from 28/20 on the boiler and wire to the switch? Do I wire 120v to it externally or is there an output on the Vitodens for this... or does the 28/20 go to the 120v connection on the zone switch?

GW

What model 200? They have what’s called an “external demand” too that can be set up

gobucks823

B2HA 28