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Need help wiring High efficiency boiler

Hi guys and girls. I'm trying to finish up the install of my new wall mount boiler. Looking for some guidance wiring the valves. The valves are older but Both work. Everything is already plumbed in just need to wire it. Attached are pictures of the valves I am using and the wiring diagram for the boiler. If someone could help me through it that would be great. The wires attached to the valves are from the old set up. I didn't want to unhook anything until it came time for reference purposes. The wires do not go anywhere after the valve they are cut. I also included a picture of the old set of (best picture I have, old traditional cast iron boiler )

Comments

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 6,141
    edited September 6
    That looks better than the previous photos. Your diagrams are here. The first one shows where the end switch(s) from the zone valves get connected to the boiler. The second one is a close up of how to connect the zone valves to the thermostat and a 24 Volt transformer. The end switches get connected to T T in parallel wiring so either zone will activate the boiler.

    If you need more help as to where to connect the boiler circulator, and the system circulator, please ask. That boiler control has a place for each item you have
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • itsbackedup
    itsbackedup Member Posts: 37
    That looks better than the previous photos. Your diagrams are here. The first one shows where the end switch(s) from the zone valves get connected to the boiler. The second one is a close up of how to connect the zone valves to the thermostat and a 24 Volt transformer. The end switches get connected to T T in parallel wiring so either zone will activate the boiler. If you need more help as to where to connect the boiler circulator, and the system circulator, please ask. That boiler control has a place for each item you have
    So should I just disregard the wiring on the valves now and start over? Wiring is not my strong suit unless it's basic stuff hot/natural stuff 
  • Zman
    Zman Member Posts: 7,472
    I would scrap it and start over. What brand and voltage are those zone valves? New power heads would freshen it all up. Installing new heads and a nice controller would give it a pro look and save you headaches down the road.
    https://www.supplyhouse.com/Taco-ZVC404-4-4-Zone-Valve-Control-Module-with-Priority
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • itsbackedup
    itsbackedup Member Posts: 37
    Zman said:
    I would scrap it and start over. What brand and voltage are those zone valves? New power heads would freshen it all up. Installing new heads and a nice controller would give it a pro look and save you headaches down the road. https://www.supplyhouse.com/Taco-ZVC404-4-4-Zone-Valve-Control-Module-with-Priority
    They are Honeywell 40004850-001 valves. So I need to order that control module? If money wasn't a problem I would put new everything and have someone come do it. Hence why I am trying to do it myself to save a little and reuse the valves. 
  • Zman
    Zman Member Posts: 7,472
    You don't have to order the controller. It is way simpler to wire the controller, especially if you are not super confidant with wiring.
    I am not familiar with that exact model valveso you should make sure you get a direct replacement part number, With the Honeywell valves I see, you can replace just the power head https://www.supplyhouse.com/Honeywell-Home-40003916-026-Replacement-Head-for-V8043E-Zone-Valves
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • itsbackedup
    itsbackedup Member Posts: 37
    Anyone have any more thoughts before I spend more money on a controller ?
  • Teemok
    Teemok Member, Email Confirmation Posts: 79
    edited September 10
    With just two zones wiring very is simple. I see a couple 24v transformers on the boxes and I'm doing some assuming. You know what that can do? Assumptions: The Transformer for the heating works, the zone valve heads have 24v motors and they both work, you have 24v thermostats with two wires each. First, power the valve motors: The transformer has two low voltage terminals. Maybe marked R and C. Start at R, connect it to both of the two t-stat wires red wires. You have two pairs of thermostat wires somewhere there right? Each with a red and white connected to the r and w terminals on the thermostat? Each one of the 2 white t-stat wires goes to power ONE of the zone valve motor power terminals. The correct t-stat wire going to the corresponding valve. The other two power terminals on the zone valves both connect together to back to C on the transformer. Now for end switches: ****None of the previous wiring is connected to this circuit wiring in any way. The two "normal open" terminals on the zone valves each wire parallel to the tt CN15 on the boiler control board. Use 18ga 2 wire. red and white. Each valve gets a red and white wire pair connected to the N.O. end switch terminals. Use the same color for same terminals on each valve. Now both reds go to one of the TT terminals on the boiler board and both whites go to the other.

    Pump: I'm guessing the "external pump" terminals are switch by the controller. One being 120V line voltage and the other is neutral. Black (HOT) and White (N). IF THAT IS TRUE, your pump wires go there. You need to know if what these terminals are before connecting anything to them. They either supply 120v Hot and Neutral or they are just a dry (isolated ) switch. One terminal to send power into (line) and the other to out to your pump (load).

    IF and only if it is a dry(isolated) switch you need to bring power to it. Make a black jumper wire to bring power down from CN18 120v, blk, hot, live to the top "external pump" switch terminal and next one down of the pair goes to (hot, line, live, 120v ) on the pump. The white from the pump connects with the other white, neutral at CN18. CN18 is on the boiler control board.

    I fear I've done too much. Hope that might help you or someone.
  • HomerJSmith
    HomerJSmith Member Posts: 2,270
    Nice solder job.
  • itsbackedup
    itsbackedup Member Posts: 37
    Teemok said:
    With just two zones wiring very is simple. I see a couple 24v transformers on the boxes and I'm doing some assuming. You know what that can do? Assumptions: The Transformer for the heating works, the zone valve heads have 24v motors and they both work, you have 24v thermostats with two wires each. First, power the valve motors: The transformer has two low voltage terminals. Maybe marked R and C. Start at R, connect it to both of the two t-stat wires red wires. You have two pairs of thermostat wires somewhere there right? Each with a red and white connected to the r and w terminals on the thermostat? Each one of the 2 white t-stat wires goes to power ONE of the zone valve motor power terminals. The correct t-stat wire going to the corresponding valve. The other two power terminals on the zone valves both connect together to back to C on the transformer. Now for end switches: ****None of the previous wiring is connected to this circuit wiring in any way. The two "normal open" terminals on the zone valves each wire parallel to the tt CN15 on the boiler control board. Use 18ga 2 wire. red and white. Each valve gets a red and white wire pair connected to the N.O. end switch terminals. Use the same color for same terminals on each valve. Now both reds go to one of the TT terminals on the boiler board and both whites go to the other. Pump: I'm guessing the "external pump" terminals are switch by the controller. One being 120V line voltage and the other is neutral. Black (HOT) and White (N). IF THAT IS TRUE, your pump wires go there. You need to know if what these terminals are before connecting anything to them. They either supply 120v Hot and Neutral or they are just a dry (isolated ) switch. One terminal to send power into (line) and the other to out to your pump (load). IF and only if it is a dry(isolated) switch you need to bring power to it. Make a black jumper wire to bring power down from CN18 120v, blk, hot, live to the top "external pump" switch terminal and next one down of the pair goes to (hot, line, live, 120v ) on the pump. The white from the pump connects with the other white, neutral at CN18. CN18 is on the boiler control board. I fear I've done too much. Hope that might help you or someone.
    You are correct these are the two thermostat wires. Not colored tho. They are both just black 
  • Teemok
    Teemok Member, Email Confirmation Posts: 79
    But one wire has writing on it. If you check your t-stat connection you can see which is on the R and W terminals. Colored tape is good to mark one. You may need to extend them with normal 18ga-2wire that is red and white. Confirm t-stats both use the the same wire as R. Just looked up the manual. The pump wires direct to the CN18 terminals with a set up "installer mode" programing change. I think from memory the top terminal of the pair is Hot but I'd test it. If you get it backwards the pump will still work, just the wire color will be wrong. Make it correct.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 6,141
    edited September 13
    Technically speaking, this bunch of wires does not meet code requirements. Not so much because there are 2 different voltages in this box, but because there are 18 gauge or smaller thermostat wires in the box.
    If you are going to run low voltage and line voltage in the same junction box, all the wires must be of the size, gauge and insulation thickness of the wire with the largest voltage and temperature rating in the box.
    That means that you need to remove the low voltage wires from the junction box and cover the box with a plate of some type, or change all the low voltage wires to a 14 gauge wire with a 105°C temperature insulation like THHN wire, and cover the box with an approved cover of some type.



    As far as getting new zone valve actuators, not necessary, As far as getting a zone valve control panel, also not necessary with only 2 zones.

    I believe my original diagram is self explanatory.

    The thermostat to zone valve to transformer wiring is basic and simple when you look at each thermostat, zone valve and transformer separately. Just do the same thing on both zones. once you have that done on both zones forget about it. It is done and has nothing to do with the boiler wires.

    Take the "END SWITCH" wires in a parallel circuit, one at a time and connect one side to a boiler T terminal. once you have all the zone valves LEFT end switch screw terminals connected. then one at a time you can connect the RIGHT ens switch terminals to the other T on the boiler. That is what parallel wiring means. that way only one of the end switches needs to close to send a call for heat to the boiler.

    This diagram is correct but may be confusing to the inexperienced. I have made some updates



    I hope this is helpful. Don't spend more money than you need to. If it ain't broke --- don't fix it!



    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    Teemok
  • itsbackedup
    itsbackedup Member Posts: 37
    Technically speaking, this bunch of wires does not meet code requirements. Not so much because there are 2 different voltages in this box, but because there are 18 gauge or smaller thermostat wires in the box. If you are going to run low voltage and line voltage in the same junction box, all the wires must be of the size, gauge and insulation thickness of the wire with the largest voltage and temperature rating in the box. That means that you need to remove the low voltage wires from the junction box and cover the box with a plate of some type, or change all the low voltage wires to a 14 gauge wire with a 105°C temperature insulation like THHN wire, and cover the box with an approved cover of some type. As far as getting new zone valve actuators, not necessary, As far as getting a zone valve control panel, also not necessary with only 2 zones. I believe my original diagram is self explanatory. The thermostat to zone valve to transformer wiring is basic and simple when you look at each thermostat, zone valve and transformer separately. Just do the same thing on both zones. once you have that done on both zones forget about it. It is done and has nothing to do with the boiler wires. Take the "END SWITCH" wires in a parallel circuit, one at a time and connect one side to a boiler T terminal. once you have all the zone valves LEFT end switch screw terminals connected. then one at a time you can connect the RIGHT ens switch terminals to the other T on the boiler. That is what parallel wiring means. that way only one of the end switches needs to close to send a call for heat to the boiler. This diagram is correct but may be confusing to the inexperienced. I have made some updates I hope this is helpful. Don't spend more money than you need to. If it ain't broke --- don't fix it!
    That junction box is no more. That was part of the old set up. Part of the reason why I'm redoing it as it was a cluster **** before. I am hoping to get working on this sunday. I appreciate diagrams. If I am showed visually how to hook it that is a no brainer. Pretty easy after that point
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 6,141
    edited September 15

    So should I just disregard the wiring on the valves now and start over? Wiring is not my strong suit unless it's basic stuff hot/natural stuff 

    YES

    That junction box is no more. That was part of the old set up. Part of the reason why I'm redoing it as it was a cluster **** before. I am hoping to get working on this sunday. I appreciate diagrams. If I am showed visually how to hook it that is a no brainer. Pretty easy after that point

    Am I correct in assuming that you will have no problem making the "BASIC STUFF" wiring to make this boiler work?

    Then this is a "BASIC STUFF" diagram for how to connect zone valves right from Honeywell Literature.
    . If you can follow the above diagram, then you can connect the zone valves to the boiler like this diagram below.

    Just take each circuit one step at a time. the key to zone valve wiring is to wire every zone the same way.

    There is more that one way to do it as you can see from the different diagrams provided, but once you pick one that you understand, then do all the other one(s) the same way. Don't swap the R for the W on the thermostat or R for the C on the transformer. It will work on one zone but swapping them on the next zone may be a problem later on when you may want to add a heating and cooling thermostat or add a WiFi thermostat that requires a common to the thermostat. I always use the R from the transformer to connect a red insulated wire to R on the thermostat. It makes it easy in the future for trouble shooting. I use the W on the thermostat to connect a white insulated wire to the motor (TH) on the zone valve. Whatever wire color is left can be used to connect the other motor wire (TR) to the C on the transformer
    .

    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    Teemok