Wiring Ecobee to Burnham boiler

TXBDan

Hello all,

I recently had a Burnham Independence IN5 boiler installed. Here are the installation instructions for reference (Electrical on Page 16):
https://s3.amazonaws.com/s3.supplyhouse.com/product_files/Burnham-SIN5LNI-LE2-Install-Instructions.pdf

I have an Ecobee 4 thermostat that i'd like to install. Here is documentation on that:
https://support.ecobee.com/hc/en-us/articles/227874667-Heat-only-2-wire-boiler-furnace-installations-for-ecobee-thermostats

I currently have only 2 wires running to the tstat to switch the boiler on/off.

I'm fine with running new wire between the tstat and boiler so adding a 3rd wire for a C wire would be fine. I could also run 4 wires which would open up the possibly of running a wall wart power supply.

What options are possible and what do you all think would be best?

Thanks a lot,
Dan

SuperTech

You can also add a common wire maker kit on the existing two wires. I have one on my van for these situations. I believe the box says something like "fast stat" on it. If you can wire a relay then you can install the kit.

HVACNUT

Your thermostat connection is with Blue and Brown at the boiler. The Yellow wires shown off the other side of the transformer is the Common you need for the EcoBee. It's a 40va transformer so you're good.

Dont add a third wire. Run a new 4 conductor wire and use the existing as a puller. You only need three wires but that fourth might be needed someday.

TXBDan

Ok, that makes sense. I see the yellow is used as C/Neutral/GND elsewhere in the circuit. Thanks!

TXBDan

I wired it up today and its working like a champ. Thanks!

4lane

I have the same issue. How did you connect your new C wire to the yellow wire exactly?

TXBDan

4lane said:

I have the same issue. How did you connect your new C wire to the yellow wire exactly?

I don't remember exactly, but i believe I ran the new 3-wire HVAC wire the same way the old 2-wire went, to a metal junction box above the boiler. I think its where the transformer is. I unscrewed a cover and inside were many wires included the yellow ones. There were two yellow wires wire-nutted together so i added the HVAC C wire to that bundle and it works. I'll double check and take a pic tonight.

Jamie Hall

Might I add... don't count on the colour coding of wires being correct. Even licensed electricians make some odd choices, now and then... test and verify.