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Taco wiring question

I cleaned up my wiring and installed a Taco 403-4 zone valve control. I have kind of a different system that was wired by a contractor that has left my area. There are 4 zones. 1 zone heats a baseboard zone on the lower level, one zone heats a baseboard zone on the upper level, one zone heats the lower level floor with radiant and 1 zone is for the domestic hot water. The previous wiring operation opened the radiant floor valve whenever one or the other or both of the two heating zones opened. I'm trying to figure out how to make the radiant zone open without adding a t-stat. This system worked great for years but it was set up with a priority relay for the domestic and on really cold days the house would get cold when the lovely bride would do laundry all day. It's a small house so running the hot water and heat at the same time isn't a big deal. what started the whole change out was a bad motor on the radiant zone valve, I just blocked it open for winter (warm floors are nice in Colorado in the winter!) but I want to get some control back. Zone valves are Honeywell V8043E1012. I wired the 2 baseboard zones and the hot water zone per Taco's diagram and they all work great. I just need to open (and close) the radiant zone whenever a heat zone calls for heat. Any help would be appreciated.

Comments

  • Rich_49
    Rich_49 Member Posts: 2,766
    edited September 2013
    Why

    didn't you purchase a ZVC 404-4 ? You could have spliced into the wires from both T Stats and run them to their own terminal to open that zone valve when either called for heat . I would change the Relay to the 404-4 . Easiest cheapest way and it will still be clean . If this worked for years it should still work . Hope this helped . 
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • Eric_32
    Eric_32 Member Posts: 267
    edited October 2013
    I agree.....

    You should have picked up a 4-zone control. You have 4-zones.... one of which needs a tsat wired or added (the radiant). If you can't run the wire, Honeywell makes wireless tstats now.



    Look in your taco box.... there's only one transformer in there. I don't know about valves you have... but Taco's 571 are limited to 3- valves max to one transformer.



    How many transformers did you have before adding the Mult-box?
  • Craig_CT
    Craig_CT Member Posts: 7
    edited November 2013
    Taco SR504 with Honeywell V8043E1020 zone valves. Troubleshooting and Best Pratice

    Hi, I have a single story ranch home with an unfinished basement below that had 2 heating zones (the 1st zone for the main living area and bedrooms, the 2nd zone for a small porch that was converted to year round space).  The floor plan is very closed so having a T-stat in the main living area does a poor job of regulating the temperature on the bedroom side of the house.  Over the summer I split the plumbing so the bedrooms would become a 3rd zone.  I installed two Honeywell V8043e1020 zone valves so I could continue using the same circulator pump. However, I never got around to doing the wiring (had other warm weather projects to attend to) so I've had the valves manually open this heating season so basically the house is still two zones.  Now that I'm back to completing the wiring I've come across an issue and would appreciate some help.  I have a Taco SR504 controlling the two zones and was going to use the 24 V lug to power the zone control valves.  When I put my multimeter on the 24 V lug on that board (I've learned the hard way to test everything before making a connection), it was outputting .3 V and the common lug was outputting 22.3 V.  Digging in a little further I found whoever installed the SR504 wired the 120 V in backwards; the hot was on the neutral lug and the neutral on the hot lug.  I corrected this and now the 24 V lug is outputting .3 V and the common lug is outputting 2.5 V.  Does anyone know if the backwards wiring could have damaged the 24V transformer that is built into the SR504?  If so, it looks like it may be a serviceable part, does anyone know if that is the case?  Could there be further damage to the board?

    Regarding my zone valves, once I can get 24 V, my plan for each valve is to put 24V to one yellow wire (yellow are motor), connect one yellow wire to a wire from the T-stat and put the other T-stat wire to a neutral.  The two red wires from the zone vale would go to the T T lugs on the SR504 where the T-stat wires had been connected.  Does this sound correct?



    Thanks in advance for any help.
  • Zman
    Zman Member Posts: 7,561
    SR 504

    I don't think the transformer or board were damaged. This is not the first time one was wired backwards.

    23.3 is a little low. What does the 120 volt circuit on the line side measure? If it is also a bit low, you don't have a malfunction.

    You need to see if the on board transformer has enough va's to run your zone valves.

    It sounds like this will work, you may need to set another transformer for the valves.

    Carl
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Dave H_2
    Dave H_2 Member Posts: 550
    ZVC controller would be best

    A Zone Valve Controller (ZVC) would be best to use here. The SR panel is meant for multiple circulators.

    The transformer on-board is designed to power the circuit board and any thermostats. It may not be large enough to handle the extra power for the zone valves.

    Your thermostats and zone valves would wire to the ZVC controller and then from there, wire the end switch to the existing SR panel to turn on the associated circ.



    Dave H.
    Dave H
  • Craig_CT
    Craig_CT Member Posts: 7
    edited November 2013
    SR504 Continued

    Line side coming in is 119.6 V.  Any thoughts as to why I only get close to 24V when wired backwards?
  • Craig_CT
    Craig_CT Member Posts: 7
    ZVC controller would be best

    Hi Dave, Thanks for your input.  As mentioned, I am wiring in two, 4 wire 24V Honeywell valves and will be adding a 3rd in the not too distant future when I finish a section of the basement.  With that said, is there a particular brand/model that you would recommend?
  • Zman
    Zman Member Posts: 7,561
    Mis-read

    Sorry I mis-read your post. At .3 the controller must not be working at all. Are you checking from hot to common or hot to ground?

    Carl
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Dave H_2
    Dave H_2 Member Posts: 550
    Taco ZVC-403

    Is a three zone/ valve contoller



    http://www.taco-hvac.com/products.html?current_category=408
    Dave H
  • Craig_CT
    Craig_CT Member Posts: 7
    Voltage

    Hi Carl,



    It's .3V when I use the common and .2V when I use the 120V line in neutral.  It seems something is wrong with the transformer that is mounted to the board and/or the board itself.  I'm going to go with Dave H's suggestion of installing a ZVC and just let a sleeping dog lie on my SR as I don't have a need for the 24V from the SR if I install a ZVC.  Thanks for your help.



    Craig
  • Craig_CT
    Craig_CT Member Posts: 7
    ZVC-403

    Thanks Dave, I'm going to pick one up over the weekend.



    Craig
  • hot_rod
    hot_rod Member Posts: 22,021
    edited November 2013
    oops wrong location

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Craig_CT
    Craig_CT Member Posts: 7
    edited November 2013
    Removed post

  • Craig_CT
    Craig_CT Member Posts: 7
    edited December 2013
    ZVC403 Voltage

    Hi Dave,

    I installed a ZVC 403-4 as you suggested and it's working as desired but I have one issue/question.  I have the X X pump end switch terminals connected to the T T terminals on zone 1 of  the SR504 to fire the circulator pump.  The odd thing is, when I ground out one probe of my multimeter and test the lugs I get 29V, I was expecting 24V.  I know fluctuations are normal, say in the 22-26 V range but I'm surprised to see this as 29V.   My line voltage in is 121V so that is almost spot on.  Does that sound normal to you?  Is there anything you know of that I should check if it's not normal?

    Thanks
  • Dave H_2
    Dave H_2 Member Posts: 550
    24 volt power

    Craig,



    24 volt power from a transformer can be higher than expected. You are OK.



    Glad everything is working well
    Dave H
This discussion has been closed.