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Basic Vitrodens wiring question

I have a Vitodens 200 with the Viessman low loss header, low loss header sensor,  Vitocell 300 53 gallon indirect tank and the Viessmann water tank sensor.  I've got all the power and sensors connected (low loss header sensor, outdoor reset, and indirect water tank sensor), but I have a question on the heating zone connections.  

What I need help with is the basic premise on connecting my four zones of baseboard heat and my four thermostats for those zones.  I think that with the Vitodens 200, the system call for heat is generated by the outdoor reset, and I *believe* that the thermostats operate simply as high temp limits for each zone (as opposed to acting as calls for heat in a normal heating system).  Is this all correct?

The next question is, how to connect the zones to the system?  I plan on using a Taco Bumble Bee delta P circulator for the heating zones, and four Taco zone valves to control each zone.  When I look at the Viessmann Power/Pump module, I see only one pump output for a heating circulator, and I don't see any inputs for the zone valves and thermostats.

Can I connect the Bumble Bee to the pump out for the heating circulator zone and, if so, how or where do I connect the zone valves and the thermostats?  I'm thinking I need something like a Taco ZVC-404 to wire the thermostats and zone valves. 

Can someone please give me just the basics of where and how the heating zone valves, Bumble Bee pump, and thermostats are wired in?  I've got most of this system well understood and this is the last part I need to understand.

And thanks in advance to all of you that have helped!  This forum's been an excellent and friendly source of info. 

Comments

  • James Day_2
    James Day_2 Member Posts: 191
    wiring

    what I do is wire the power form the vitotronic pump module through the endswitch in the zone control box.  Your system pump in viessmann world is going to run all the time.  By wiring through your zone control your thermostats are going to turn your system pump on and off as needed.  Your boiler pump will work off the temperature in the LLH.    

    James
  • veissman_Bob
    veissman_Bob Member Posts: 48
    Thank You!

    So if I'm reading this correctly, I'm going to wire from the Vitodens Power Pump Module terminal 20A (System Pump) to the Taco ZVC-404 "main end switch" (which also has  a note that reads "to circulator or aquastat relay"), correct? 

    Terminal 20A looks like it has three inputs whereas the ZVC-404 "main end switch" only has two inputs.  Any polarity or other issues to worry about with this connection?  Or do I just use any two terminals on Vitodens 20A output, and connect them to the two ZVC-404 "main end switch" inputs?

    After the system pump is connected as above, then I simply wire the four thermostats into the four thermostat inputs, and the zone valves to the zone valve outputs?

    And connecting in this manner will keep the system pump off when there's no need for heat, but run when any of the four zones requires it?

    Taco also makes a six zone controller that also has inputs for the water heater pump and the boiler pump but it sounds like the Vitodens can controll those to pumps fine.

    Thanks for taking the time to read and think about this for me. 
  • veissman_Bob
    veissman_Bob Member Posts: 48
    I'm rethinking this...

    I'm rethinking this and I think the answer is that I don't use output 20A on the Vitodens at all.  I think all I do is wire the thermostats and control valves as above, and connect the system circulator to the "main end switch" on the Taco.  When a zone calls for heat, the Taco ZVC-404 will open the corresponding zone valve; once the zone valve is fully opened, the "main end switch" is energized and the heating circulator will turn on.



    I think the only reason you would use the 20A output on the Vitodens is if you were running the system on outdoor reset only and with one zone.

    Can anyone tell me if that's the correct way to wire this up?
  • CMadatMe
    CMadatMe Member Posts: 3,086
    edited September 2011
    You Got It

    There is no TT connection on Vitodens 200. Since we are not running a constant circulation system we wire nothing to the PPM except for our boiler and dhw pumps. You simply follow the wiring diagram inside the cover of the Taco ZVC control and wire in the system pump as you noted.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • James Day_2
    James Day_2 Member Posts: 191
    Wiring

    Wouldn't we want to wire the system pump from the ppm through the end switch on the zone control this way if dhw calls the boiler ppm will kill the system pump.
  • veissman_Bob
    veissman_Bob Member Posts: 48
    Thank you

    to everyone who provided advice.  I spoke to Viessmann directly and was told that the preferred wiring method is to wire the system pump through 20A but when using zone valves this is only possible if the system pump can withstand being deadheaded against closed valves.  This situation could occur if the outdoor reset was calling for heat while the individual zone valves were closed.  Some of the better pumps such as the Grundfos Alpha and the Wilo Stratos can supposedly handle a deadhead situation.  I need to check and see if the system pump I'm using (Taco Bumble Bee) can take a deadhead situation.

    If it can't, then the correct way to do it is to wire the pump to the TT end switch of the zone valve control.  In this case, the pump won't be energized until at least one valve is open.  The disadvantage in wiring through the zone valve control instead of through the Viessman Power Pump Module is that you lose some features of the Vitodens contol, namely the ability for the Viessmann control to periodically exercise the pump, and the prioritization of the indirect water heater during calls for water heating (although this also can be wired through the zone control).

    I think I've got it covered now but if any of the experts on this board have any comments or other suggestions, I'd love to hear them.
  • veissman_Bob
    veissman_Bob Member Posts: 48
    Thank you

    to everyone who provided advice.  I spoke to Viessmann directly and was told that the preferred wiring method is to wire the system pump through 20A but when using zone valves this is only possible if the system pump can withstand being deadheaded against closed valves.  This situation could occur if the outdoor reset was calling for heat while the individual zone valves were closed.  Some of the better pumps such as the Grundfos Alpha and the Wilo Stratos can supposedly handle a deadhead situation.  I need to check and see if the system pump I'm using (Taco Bumble Bee) can take a deadhead situation.

    If it can't, then the correct way to do it is to wire the pump to the TT end switch of the zone valve control.  In this case, the pump won't be energized until at least one valve is open.  The disadvantage in wiring through the zone valve control instead of through the Viessman Power Pump Module is that you lose some features of the Vitodens contol, namely the ability for the Viessmann control to periodically exercise the pump, and the prioritization of the indirect water heater during calls for water heating (although this also can be wired through the zone control).

    I think I've got it covered now but if any of the experts on this board have any comments or other suggestions, I'd love to hear them.
  • CMadatMe
    CMadatMe Member Posts: 3,086
    edited October 2011
    Domestic

    Why would you zone dhw on the system side of the LLH? Indirect should be piped on the boiler side in order to provide priority and to have the ability to use the controls full DHW program. We never never use the 20a plug unless we are running a constant circulation system. I have to disagree with the tech at Viessmann on this. Not the best answer. If you are zoning pumps Taco makes a pump exercise card for the exp zone control. You can also use it on a ZVC-exp zone control to exercise a system pump.



    Even though you have DHW down stream of the LLH you still use the 21 plug,. You have

    to change in coding 1 address A2 to 0 and in coding 2 address 5b to 1. Your giving up priority. When in priority the boiler shuts down the 20 plug (boiler pump) and the indirect pump becomes the boiler and domestic pump. That is why we pipe DHw on boiler side of the LLH. Domestic pump gets piped into the domestic return up stream of the boiler pump.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • veissman_Bob
    veissman_Bob Member Posts: 48
    Indirect piping

    Hello Chris, thanks for the advice. I'm not planning on connecting the indirect downstream, it's going to be piped directly off the boiler before the LLH.  As for the system pump, I'm going to check with Taco tomorrow to see if the Bumble Bee can handle deadheading, but I'm leaning towards powering it off a basic ZVC-404.  Exercising the pump isn't all that important to me, it's just one of the available features I'd lose if I didn't use 20A.

    The feeling I'm getting from this board is that most people bypass 20A in a zoned system and allow the zone valve control to power the system pump on and off via the end switch.
  • CMadatMe
    CMadatMe Member Posts: 3,086
    edited October 2011
    Confused

    Bob by your post it sounded as though you had. Sorry for the confusion. Since that bee is a beta model you may be testing the waters for them. Don't use the 20a plug much at all.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
This discussion has been closed.