1 Thermostat 2 Zone valves

ceksenior

I have a 5 zone heating system. 4 hot water zones and 1 steam zone. The boiler is a Burnham Independance IN5 . The Zone valves are Honeywells part # V8043E1012. The thermostats are Honeywells part # TH4110D1007.

I am going to take a wall down in my home and I want to combine 2 Zones into 1.

I dont have access to the Pex piping to combine the zones in 1 loop and was wondering if I can use 1 thermostat to open and close 2 zone valves.

Any help would be greatly appreciated.

Alan (California Radiant) Forbes

Combining

It shouldn't be a problem.  If you have a zone valve controller, just wire the two zone valves to one thermostat along with the end switches.



Here is a sample wiring diagram:



http://www.taco-hvac.com/uploads/FileLibrary/102-092.pdf

ceksenior

No controller

I appreciate the reply but I dont have a zone valve controller like the one in the diagram you included. All zone valves are on a manifold and approx 4 inches apart from each other. All the wires go into a electrical box with 2 contactors and a 24v transformer and allot of wires.

Alan (California Radiant) Forbes

Consider

You should consider upgrading to a zone controller.  It makes wiring a snap and diagnosing a problem easy. 



You have got to locate and isolate the wiring to those two zone valves and remove the 24 volt wiring from the zone valve you want to disable and bring two wires over from the active zone valve and wire them in series with the one that had the wiring removed.  Don't touch the end switch wires.

ceksenior

I have photos

Yes hooking up a controller would be ideal but For now Im going to try and hook it up the way it is.



When i took off the covers Its just allot of speghetti with unmarked wires. I dont want to screw up a system that at this point works perfect. I included pictures which Im hoping will make it more clear how my system looks.  Which box should I connect the wires in series. And how would I do this. Each zone valve has 2 red wires and 2 yellow wires. Ther thermostats have 1 red and 1 white. There are also a series of black wires running from 1 box to another.



Any help would be much appreciated.

ceksenior

A liitle more assistance

I just need a little more assistance please. Which wires are the 24v supply and which are the end switch. There are 2 red and 2 yellow comming out of the zone valve.

Alan (California Radiant) Forbes

Assistance

Before I go on, I want to say that you have entered the realm of work that should be done by a skilled technician and that if you want to DIY it, you do so at your own risk.  If you connect the wiring incorrectly, you can burn out the transformer.



The yellow wires are the ones that power the motor and the red ones are the end switch.  Make sure by following the leads - the yellow ones should go to the motor.  Inside, they may have wire nuts to other leads that change color.



The smaller box is where I would switch the wires.  Make sure the power is off when the work is done.

ceksenior

Thanks Alan

I appreciate your input. Although I am a novice in my boiler room I am not a DIYer when it comes to reading wiring schematics.



I went on honeywells site and brought up the installation instructions for my valve. This helped a great deal.



I see that the valve is powered in series with the transformer and the thermostat. The thermostat acting as a switch to complete the circuit to power the motor in the valve. I also saw what the end switch does. This is simply a switch which provides continuity across the two terminals whenever the zone valve is open.



I do have one last question though. Is it safe to assume that if one of the zone valves fail it will render the other valve inoperable since they are run in series?

Also, since there will a voltage drop across each motor, will there be a sufficient voltage to open the valves?

Mike Kusiak_2

Parallel motor wiring?

Alan, don't you want to wire the two zone valve motors in parallel? If you connect them in series each motor will receive only 12 volts instead of 24.

Alan (California Radiant) Forbes

Mike and SEK

Maybe I'm wrong here, but what I envisioned is the two wires from the thermostat/transformer going to the first zone valve and then two more wires going from the first zone valve to the second zone valve.



If the first zone valve is broken and doesn't turn on, the second zone valve would still work.



Drop in voltage? I don't see it.

Mike Kusiak_2

Parallel motors

Alan, I think we are saying the same thing, just a difference in terminology. If you connect the two wires from each motor together, and then connect them to the two wires from the transformer and thermostat, that is considered a parallel connection and both get the full 24V. I think that is what you are describing.



A series connection of motors would be that only one wire from each motor were connected together, and the remaining two wires would be connected to the transformer and thermostat. In this case, each motor would only get 12V since the voltage would divide between them.



To a person with an electrical background, a series connection has a very specific meaning, which is why we were both a bit confused.

ceksenior

Are we all in consensus

All Im going to do is wire the other motor parallel to the wiring going to the motor of the valve in which the thermostat and transformer will be connected.



And Im not removing any wires from the end switchs of either of the zone valves, Correct?

RobbieDo

Relays

The best way to do this is relays, I am a Electrician and HVAC tech, I am self employed. I install most of my own controls I design myself or use PLCs. If you want I cam email you a schematic to do this but if you don't follow it properly it won't work.

ceksenior

Relay

Cool. I have 24volt relays at work. Im assuming that I would pigtail a wire off the thermostat controlled zone valve motor as the switch end of the relay from the (NO) contacts and power up the other zone valve directly off the transformer.



Is that what you had in mind.

Mike Kusiak_2

Relay

Why not drive the relay coil directly from the thermostat and use the NO relay contacts to switch both motors in parallel, fed directly from the transformer. That way you will eliminate the voltage drop in the thermostat wiring and reduce the current it has to switch to just that of the relay coil.

ceksenior

Spoiled

I looked quickly at the wiring sunday morning B4 the wifes honeydoos. I guess becuase Im spoiled at work with labeled wires and detailed schematics, but Im havin a hard time figuring which wires go where.



I really have to sit down with a multimeter and disconnect wires and check for continuity to distinguish wires B4 I can decide which way Im hooking this up.



I was hoping I could just hook up the motor wires in parallel and be done with it.

Alan (California Radiant) Forbes

Mike and SEK

Thanks for the clarification, Mike. Parallel it is.



And SEK, you should carry on with your original plan:



"All Im going to do is wire the other motor parallel to the wiring going

to the motor of the valve in which the thermostat and transformer will

be connected."







And leave the end switches as they are.



What you have there is a jumble of wires, what I call a rat's nest.  It will help you and others that come after you to have a wiring diagram on the boiler room wall along with a "Sequence of Operation" that explains how all the devices work on a call for heat.



So get a piece of paper, trace each wire and diagram it.  After a while, the fog will clear and you will know exactly how your system works.

ceksenior

Thanks Alan

Wired it up this morning works perfect.



When the weather gets warmer Im going to look into getting a 24v zone controller.