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Final call for heat…

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Hi everyone.

You guys have been awesome, thus far, but I need one last push…

I am going to attach the final primitive schematic I just made of the wiring of four taco zone valves, with 2x 24 V transformers. Two thermostats per transformer.

As Ed had said (it even rhymes!), I started with one zone and got that working, but when I added the next zone, everything stopped working, so I figured something must’ve not been wired correctly.

Turned out I now have a dead transformer (the heads works on one transformer, but not the other)… So when I took the single zone over to the other transformer, it worked fine.

In an effort not to blow up another transformer, and leave me a completely without heat, would you be willing to look at this diagram and see if anything looks at awry?

Does this look like it will not blow anything up?

The only thing that wasn’t clear from all the diagrams you guys have shown from before, which I appreciate, is exactly how to wire the TT, particularly the common side of it. Does this look OK?

I’m really hoping you guys can take a look at this and tell me if there’s anything that’s not going to work properly…

Thank you!




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Comments

  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,

    I'd have to look at old posts but I think you are doing it again. When the thermostat closes (call for heat) it shorts out the transformer. Not correct.




    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • Big Ed_4
    Big Ed_4 Member Posts: 2,805
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    It looks wrong . What control is being used between thermostat and zone valve ?

    There was an error rendering this rich post.

  • WhirlingD
    WhirlingD Member Posts: 78
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    I have one zone working with this basic premise now…

    I’m not sure what you guys are seeing. Thoughts?
  • WhirlingD
    WhirlingD Member Posts: 78
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    109A_5 said:

    Hello @WhirlingD,

    I'd have to look at old posts but I think you are doing it again. When the thermostat closes (call for heat) it shorts out the transformer. Not correct.




    Can you tell me specifically what you are seeing?

  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,
    What we are seeing is incorrect wiring which you proved by killing a transformer. To me you are trying to hard to make the Wago things work instead of making the circuit work correctly. The thermostat switches the load ONLY which is the motor in the zone valve. Only loop per zone on the control side.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • pedmec
    pedmec Member Posts: 987
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    Where's your common (w) on the right hand transformer?

    (w) out of the thermostats should go to #1 on power head. #2 can be spliced together. you're shorting the transformer in the pic.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,613
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    @WhirlingD

    WHAT KIND OF ZONE VALVES DO YOU HAVE?
    Are they 3 wire Taco valves?
  • WhirlingD
    WhirlingD Member Posts: 78
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    @WhirlingD

    WHAT KIND OF ZONE VALVES DO YOU HAVE?
    Are they 3 wire Taco valves?

    Yes, three terminal taco valves.

  • WhirlingD
    WhirlingD Member Posts: 78
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    pedmec said:

    Where's your common (w) on the right hand transformer?

    (w) out of the thermostats should go to #1 on power head. #2 can be spliced together. you're shorting the transformer in the pic.

    Oh, sorry, I just left off the diagram… It runs to the Connector with the other Whites, same as the other side.
  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,
    Maybe something like this.


    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,


    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • WhirlingD
    WhirlingD Member Posts: 78
    edited November 2023
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    109A_5 said:

    Hello @WhirlingD,
    Maybe something like this.


    Thanks!

    Was the only change you made… the right hand White going from the transformer down to the common in White Connector?

    I think that’s what I was devising, but just forgot to write in that white wire

    Was there anything else that you added to the diagram?

  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,

    Yes, I changed both sides Left and Right. Also added the missing White wire (Right side). Count the wires at each connection node from your original compared to my updated drawing. Then understand why they go where they go.

    Maybe forget the colors.


    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • WhirlingD
    WhirlingD Member Posts: 78
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    109A_5 said:

    Hello @WhirlingD,


    This would fry the transformer, because there’s no load on the circuit that you’ve drawn on here?

    I didn’t think I had that when I tried to add the second zone to the circuit, but I have it unwired now, and can’t tell. I thought I was pretty careful to do this:

    Transformer red wire to connector that branched out to both red wires of thermostats…

    White wire from thermostats branched out to a Connector, which led to both first top terminals of taco zone valves.

    Both white wires of zone valves went to a Connector that went back up to the white wire of the transformer, and another white wire going off of The Connector to the white wire of the TT burner control.

    The green wire of TT went to a Connector that branched out to both third terminals of taco valves.

    Does that sound about right so far?

    To add the other two zone valves in, and thermostats, I was just going to do them in the exact same way, But have another white wire coming off of the connector from TT that would lead to the main white wire connector in the second set that’s pictured on the right.

    If I’m understanding you correctly, based on the addition that you put on my diagram, they should be just about right?

    Forgive me, that I am trying to put all this together based on what you guys have shown, and what I have learned through research.

    At least I have one zone working for tonight, and I’m finding that even with one zone working, I can keep the house from getting completely iced out… :-) 🥶🥶

    At least for now… :-)

  • WhirlingD
    WhirlingD Member Posts: 78
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    109A_5 said:

    Hello @WhirlingD,

    Yes, I changed both sides Left and Right. Also added the missing White wire (Right side). Count the wires at each connection node from your original compared to my updated drawing. Then understand why they go where they go.

    Maybe forget the colors.


    I think I see what you did now…

    You took the common wire from the thermostat, and instead of going to a Connector, which could lead right back to the transformer, you went directly down to the corresponding zone valve.

    Is that the problem that you fixed with your new diagram?

  • 109A_5
    109A_5 Member Posts: 1,387
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    Hello @WhirlingD,
    Yes, and both sides now match, at least on the updated drawing.

    A circuit is a loop or a circle. Power source (transformer), Control device (thermostat), Load (zone valve motor). When you add extra paths (wires) that are not needed, the only needed loop is compromised and you get problems.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • 109A_5
    109A_5 Member Posts: 1,387
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    WhirlingD said:

    109A_5 said:

    Hello @WhirlingD,


    WhirlingD said:

    This would fry the transformer, because there’s no load on the circuit that you’ve drawn on here?

    Yes
    I didn’t think I had that when I tried to add the second zone to the circuit, but I have it unwired now, and can’t tell. I thought I was pretty careful to do this:
    I can't speak to the way you wired it only the drawing you presented.
    Transformer red wire to connector that branched out to both red wires of thermostats…
    Yes and only to the thermostats. You had it also going to the zone valves too
    White wire from thermostats branched out to a Connector, which led to both first top terminals of taco zone valves.
    This was wrong, since that connector went back to the transformer too.
    Both white wires of zone valves went to a Connector that went back up to the white wire of the transformer, and another white wire going off of The Connector to the white wire of the TT burner control.
    This was OK.
    The green wire of TT went to a Connector that branched out to both third terminals of taco valves.
    This was OK.
    Does that sound about right so far?
    See above.
    To add the other two zone valves in, and thermostats, I was just going to do them in the exact same way, But have another white wire coming off of the connector from TT that would lead to the main white wire connector in the second set that’s pictured on the right.
    Yes
    If I’m understanding you correctly, based on the addition that you put on my diagram, they should be just about right?
    Yes
    Forgive me, that I am trying to put all this together based on what you guys have shown, and what I have learned through research.
    No problem.

    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • Steamhead
    Steamhead Member Posts: 16,889
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    What I'd do is have the wires from terminal 3 of each set of ZVs go to an isolation relay- one relay for each set of ZVs. The Terminal 3 leads go to one side of the relay coil and the other coil terminal goes to the C (W on your diagram) terminal on the transformer. Both sets of relay contacts then go to TT on the boiler.

    The Honeywell or Resideo R8222B or D is a good choice here.

    This completely sidesteps the fried-transformer problem.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    hot_rod
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,613
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    @WhirlingD See the attached wiring diagram.

    What you are doing is complicated even for a technician. I agree with @Steamhead I like using relays and I use the Rib relays with a pilot light so I can see what is going on.

    But it will work with out relays if you follow the diagram. I will also attach the Taco brochure.
  • 109A_5
    109A_5 Member Posts: 1,387
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    @Steamhead, @EBEBRATT-Ed

    No amount of relays would have saved the day. In fact it probably would made it worse, more items to miswsire. @WhirlingD apparently had it wired so when the thermostat closed it shorted out the transformer. This was covered in a previous post. And the correct wiring method was there too.




    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • hot_rod
    hot_rod Member Posts: 22,254
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    You should relay just buy a 6 zone relay box.

    Two separate transformers feeding 3 wire valves trying to complete the TT dry contacts is not going to be easy.
    You do not want to put voltage on TT, it just needs a closure
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • WhirlingD
    WhirlingD Member Posts: 78
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    hot_rod said:

    You should relay just buy a 6 zone relay box.

    Two separate transformers feeding 3 wire valves trying to complete the TT dry contacts is not going to be easy.
    You do not want to put voltage on TT, it just needs a closure

    Yeah, you are right, and in a less mean and cruel world, that’s exactly what I would do… But I am penniless, so I have to scrape and barter to get this up and working…

    I’m still going to need another stupid zone valve head, because I have one not working… And I’ll bet I’ve replaced four or five of these things in the last three years. These things seem pretty useless and fail fairly quickly.

    Of course, I don’t really know if I fried one of these things by wiring it incorrectly the other day. My bad. 😵‍💫😤
  • WhirlingD
    WhirlingD Member Posts: 78
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    Hi all… Update.

    Thank you all for your invaluable help.

    I now have two out of four zones working perfectly, off of the one working 24 V transformer. Hooray!

    I just got a new transformer from the local electric supply place for the other two zones. But it’s unclear how to wire the thing for the remaining two zones.

    This thing has three terminals on it, with arrows pointing to the two outside terminals for 24 V. OK.


    But unlike the other transformer, it’s unclear which one I should be using for common, and which one is hot. The other one was clearly labeled.

    I would think that wiring this wrong would create an opposite polarity? Clearly, I don’t understand the basics of electricity!

    I will attach a photo, if you guys can help clarify which terminal gets red in which terminal gets white.

    Thank you again!
  • ethicalpaul
    ethicalpaul Member Posts: 5,728
    edited November 2023
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    It doesn't matter. Attach to the two lower lugs to get 24vac

    Here is a place to learn about ac vs dc: https://learn.sparkfun.com/tutorials/alternating-current-ac-vs-direct-current-dc/all
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • Jamie Hall
    Jamie Hall Member Posts: 23,428
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    But don't even try to parallel that transformer with your other transformer. Keep the circuits quite separate.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • WhirlingD
    WhirlingD Member Posts: 78
    edited November 2023
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    But don't even try to parallel that transformer with your other transformer. Keep the circuits quite separate.

    Thank you.

    It’s my understanding that if I needed to, I could get three zone valves and thermostats running off of one transformer.

    My plan is to leave the two working circuits alone on the one transformer, and put the two remaining on this transformer after I get it installed.
  • WhirlingD
    WhirlingD Member Posts: 78
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    It doesn't matter. Attach to the two lower lugs to get 24vac

    Here is a place to learn about ac vs dc: https://learn.sparkfun.com/tutorials/alternating-current-ac-vs-direct-current-dc/all

    Thank you, Paul…

    Somehow, I would have thought that things would be reversed… Opens would be closed and closed would be open…

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,613
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    Taco says and they are correct that you can intermingle the transformer wiring (there are two transformers plus T &T on the control which adds a third transformer.

    This will work because you only have 1 wire from each transformer intermingled.

    I never liked that set up but it will work. But it is difficult to troubleshoot when something goes wrong.

    I much prefer relays with idiot lights like a RIB Rubu1C. Or a relay panel. It makes it much easier to understand and it is much more straight forward and easier to work on. And with lights it is much easier to
    see what is going on.

    Your choice.

    Look at the taco brochure I posted and read it it explains perfectly why this will work without any relays if that is the way you want to go
  • WhirlingD
    WhirlingD Member Posts: 78
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    Taco says and they are correct that you can intermingle the transformer wiring (there are two transformers plus T &T on the control which adds a third transformer.

    This will work because you only have 1 wire from each transformer intermingled.

    I never liked that set up but it will work. But it is difficult to troubleshoot when something goes wrong.

    I much prefer relays with idiot lights like a RIB Rubu1C. Or a relay panel. It makes it much easier to understand and it is much more straight forward and easier to work on. And with lights it is much easier to
    see what is going on.

    Your choice.

    Look at the taco brochure I posted and read it it explains perfectly why this will work without any relays if that is the way you want to go

    Thank you for your thoughts.

    In a kinder gentler world, I would consider going for one of those relay panels in a heartbeat..

    I’ve replaced more zone valves over the last five years than I care to remember… And I’m sure that will continue.

    But I’m on a very limited fixed income, and even 200 bucks plus some change is a significant amount, when I just spent $670 on a new boiler controller last week.

    Plus, outside of that boiler controller, I pretty much know how the system works now, so it won’t be as hard to troubleshoot next time it gets all fouled up like this.



  • tim smith
    tim smith Member Posts: 2,765
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    here is clip out of cutsheet for Taco ZV. Gives you a clean look at it. I know the document was shared above but here it is.
  • WhirlingD
    WhirlingD Member Posts: 78
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    OK… Onto the next step.

    I went down to install the transformer, and here’s what I found.

    The whole transformer circuit is only a two wire set up, and my new transformer has three… Black, white green.

    I also found that the wires go into nuts and one black and white go right next-door to the other transformer, meaning that I believe they are wired in parallel. There are two transformers wired from one feed.

    Is that the way I would want this to go? I would suspect yes?

    I presume I would just wire the new transformer in just like the old one?

    What do I do with the green wire coming off the new transformer?

    You guys have been great… Thank you! Hopefully, this will be the last step! Provided of course, everything works when I get it put together… :-)
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,613
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    @WhirlingD Use black and whit on the new transformer for the 120 volt feed. Black hot and white neutral. The transformers are in parallel on the primary side that is fine.

    Then use the bottom two connections for your 24volts as @ethicalpaul pointed out.

    If the transformer is mounted on a metal outlet box you can ignore the green it's the safety ground, Or connect it to one of the box mounting screws. It wouldn't be a bad Idea to put a fuse in the 24v hot wire from each transformer incase something is screwed up you wont destroy another transformer. It should be a 2 amp fuse.
    ethicalpaul
  • WhirlingD
    WhirlingD Member Posts: 78
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    @WhirlingD Use black and whit on the new transformer for the 120 volt feed. Black hot and white neutral. The transformers are in parallel on the primary side that is fine.

    Then use the bottom two connections for your 24volts as @ethicalpaul pointed out.

    If the transformer is mounted on a metal outlet box you can ignore the green it's the safety ground, Or connect it to one of the box mounting screws. It wouldn't be a bad Idea to put a fuse in the 24v hot wire from each transformer incase something is screwed up you wont destroy another transformer. It should be a 2 amp fuse.

    Excellent. Thank you so much for your help!

    When I get it all up and operational, I’ll let you know that I haven’t blown anything up… :-)
    ethicalpaul
  • WhirlingD
    WhirlingD Member Posts: 78
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    OK everybody… I still can’t finish this job… There’s one more caution sign…

    Given that I have two separate sides of my zone wiring… Two zones on one transformer and two zones on the other, and both go to TT, I’m not sure what to do with the ground wire coming off of TT for the second circuit.

    In the left-hand circuit of this diagram, it’s working perfectly. I am about to finish the wiring for the right, but I don’t yet have the TT ground connected directly to the right side circuit.

    In my diagram, in the center, it shows the main white wire coming off of TT going into a connector which branches out into the main ground of the right side circuit, as well as to the left circuit.

    Is this actually necessary?

    Given that TT is grounded in the left circuit, does it still need to be grounded in the right circuit?

    Hope you guys can help for one last, last time!




  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,053
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    Have you considered using one of these?https://www.supplyhouse.com/Taco-ZVC404-4-4-Zone-Valve-Control-Module-with-Priority
    It will eliminate all the guess work
    It has fuses built in (SMOKE KEEPERS)
    every component has a location that is clearly marked. Thermostat, Zone Valve, Boiler Control
    The transformer(s) are included.

    There is very little room for error
    LED lights indicate what parts are working and what parts may have failed for easy problem diagnosing.

    In the illustration below, I have indicated what other features you do not need in order to make the job easier.
    On the bottom row they illustrate different types of zone valves. Since you only have the three wire zone valve, I faded out the others and will tell you to connect ALL 4 of your zone valves in the way the 3 wire valve is connected to zone 2 on the diagram

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,053
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    If you are going to try to connect each zone valve the correct way without the control above, then I suggest that you connect one valve at a time and test it. You have one of the valves working and I believe that you have it wired this way.
    The next step is to get the second zone valve and thermostat to do the same thing.
    I have used the TACO diagram form the instructions below. I have added the colors to indicate the same wires as above.

    Don't let the direction of the boiler end switch confuse you. The wires are the same even if that are on the left or the right. and I only put the colors on the thermostat side of the diagram. I left the wires from the end switch to the boiler the original black from the factory diagram.

    To connect the second zone valve you need 4 wires that I have indicated with thicker lines.
    RED The R from the transformer goes to the R on the thermostat.
    WHITE The W from the thermostat goes to the 1 on the zone valve for the second zone.
    BLUE The 2 from the second zone valve goes to the C on the transformer (or 2 on the first zone valve).
    BLACK And the black from 3 on the second zone valve gets connected to 3 on the first zone valve.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • WhirlingD
    WhirlingD Member Posts: 78
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    If you are going to try to connect each zone valve the correct way without the control above, then I suggest that you connect one valve at a time and test it. You have one of the valves working and I believe that you have it wired this way.
    The next step is to get the second zone valve and thermostat to do the same thing.
    I have used the TACO diagram form the instructions below. I have added the colors to indicate the same wires as above.

    Don't let the direction of the boiler end switch confuse you. The wires are the same even if that are on the left or the right. and I only put the colors on the thermostat side of the diagram. I left the wires from the end switch to the boiler the original black from the factory diagram.

    To connect the second zone valve you need 4 wires that I have indicated with thicker lines.
    RED The R from the transformer goes to the R on the thermostat.
    WHITE The W from the thermostat goes to the 1 on the zone valve for the second zone.
    BLUE The 2 from the second zone valve goes to the C on the transformer (or 2 on the first zone valve).
    BLACK And the black from 3 on the second zone valve gets connected to 3 on the first zone valve.

    Thank you Ed. I appreciate your input.

    However, I already have two zones working perfectly attached to one transformer.

    The other two zone heads are going to be attached to the other transformer.

    My question is: do I have to intermingle the TT ground wire from one 2 valve head circuit to the other?

    The TT white wire is sent to the ground circuit on the left side of the diagram, and this diagram also shows it going to a connector and going to the right side ground loop.

    Do I have to have TT white wire connecting to both independent circuits? I’m presuming I do, but I’d like your verification of that first before I blow something else up… 😤😵‍💫🤦‍♂️

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,053
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    Once you get that done, you can go to the other two with your new transformer. Did you get some fuses yet?

    You will need to decide what terminals are R and C on your replacement transformer. I'll help


    You should write those letters on the transformer with a sharpie

    Now do the same thing on zone valve number 3 as you did on zone valve number 1 (Step 3). except do not connect the end switch yet. Then do the same thing with zone valve number 4 as you did with number 2 (Step 4). Then connect the end switch to the number one zone valve Not the T T , it must be 2 to 2 and 3 to 3. (Step 5)

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,613
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    @WhirlingD

    It seems we have been through this several times. Go back to my post on 11/12 and look at the taco valve brochure. It explains how you can comingle the transformers and why it works and shows multiple transformers and multiple zone valves. What else do you need? Just follow that diagram.

    I would follow @EdTheHeaterMan advise to get 1 side working at a time then maybe disconnect that side and hook up the other side and if they both work then comingle them. And use fuses as he suggested.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,053
    edited November 2023
    Options
    @WhirlingD
    My question is: do I have to intermingle the TT ground wire from one 2 valve head circuit to the other?

    Yes, the #2 on the first two zone valves MUST be connected to the #2 on the second two zone valves.
    And the number 3 on the first two zone valves MUST be connected to the number 3 on the second zone valves.

    This is the only way to properly connect intermingle both transformers with the heating system transformer. (there are 3 transformers involved here and if you don't follow this wiring procedure, you will have SMOKE problems. or fuse problems if you use the SMOKE KEEPER Fuse.)

    The TT white wire is sent to the ground circuit on the left side of the diagram, and this diagram also shows it going to a connector and going to the right side ground loop.
    .Everyone else please hold your ears

    THE TT WHITE WIRE

    FROM THE W ON THE THERMOSTAT GOES TO NUMBER 1 TERMINAL ON THE CORROSPONDING ZONE VALVE. NO WHERE ELSE!

    There is No Ground on 24 VAC side of a transformer. (occasionally the COM is also attached to the case but it is not Ground as you are thinking of... So do not use the term Ground when referring to Common. I believe that may be part of your confusion).

    Follow the diagram one step at a time. If you have 2 zone valves working and you did not follow MY diagram, there will be problems when you connect the second transformer.

    There is more that one way to get this to work. BUT if you use one way that works with another way that works on the same heater, you will have problems. Once you select one design, you must use that same design throughout ALL zone valves.

    This has been a problem with 3 wire zone valves since they were introduced in the 1950s (or earlier) For the savings of one screw terminal on that valve (times the millions of valves made) there has been electricians, plumbers, and handymen that have been confounded by this valve. You are not the first... and you will not be the last.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?