NO 'C' Wire on my Taco switch!Options to connect Ecobee?

[Hope]

Hello,

I ordered an ecobee thermostat. Now that it has arrived, I have found out I only have two wires R and W going into my thermostat. I have a tankless combi boiler which provides me hot water and fulfills my heating needs. I have 4 zones and all thermostats are connected with two wires. In the setup right next to the boiler, I have a TACO SR 506 switching relay. There is a wire coming from the tankless boiler goes to R and W. and outgoing wires (4x) are only connected to R and W terminals on the switch. Its important to note that the wire coming from the boiler has three extra wires clipped on both sides.


I wanted to install ecobee on one of the zones (Eventually I want to have wifi thermostats on all 4 zones). After talking to ecobee customer support, I have learned that I need to run a ‘C’ wire. Now if there was a C wire outlet on my switch, it will be easier to just run a C wire to the thermostat? Is there a way to get a C wire out of the switch? I am novice to this stuff and feel like I have kind of hit a wall.

Thanks for your help.

 

[Stuff]

On the left you can see the green terminals. "COM" is C. Looks like all the thermostat feeds are two wire. You can run new thermostat cables or else get a "common maker" or "add-a-wire" device. The Ecobee PEK won't help as it needs 3 wires.

 

[Sponsor]

 

[Hope]

So if I run new thermostat cables for all thermostats because I would like all four zones to have wifi thermostats in the future. How will I get C wires for all four of them? There is only one COM terminal? How easy/hard it would be to run thermostat cables? I have one thermostat in basement very close to the taco switch, two are on the first floor and one is on the second floor.

 

[Reach4]

So if I run new thermostat cables for all thermostats because I would like all four zones to have wifi thermostats in the future. How will I get C wires for all four of them? There is only one COM terminal?

Splice wires together.

How easy/hard it would be to run thermostat cables?

What are you asking? Are you asking how hard it is to fish concealed thermostat wiring through walls? You may want to hire that out, because experience helps a lot in doing the job without doing damage.

 

[Hope]

Splice wires together.

Thanks for your reply. I guess I wanted to know will it be able to power 3 or 4 wifi thermostats (preferably ecobees) because its only one 24 v terminal.

What are you asking? Are you asking how hard it is to fish concealed thermostat wiring through walls? You may want to hire that out, because experience helps a lot in doing the job without doing damage.

I think it would be better to hire someone to fish the wires for me.

 

[Stuff]

Thanks for your reply. I guess I wanted to know will it be able to power 3 or 4 wifi thermostats (preferably ecobees) because its only one 24 v terminal.

I believe the Taco has a 40VA transformer (the 2 zone version only has 15VA). The specs state that an active zone needs 4VA. Each smart thermostat needs 3-5VA. So 4 zones = 4*(4+5)=36 and you should be fine.