Common Maker Thermostat Wire Extender (Adds a Common C Connection)

I have a large 5 zone heat only system, the 2 wire thermostat wire was wired when the house was built and goes through very small holes and is stapled to the wood framing. I purchased a roll of 3 wire 18 gauge, I was able to re-wire two zones on the first floor, but unable to re-wire the 2nd floor and one zone that is the other end of the house. Using the old wire to pull new wire through would not have worked, as the old wire is stapled to frame and the holes are just enough to feed the wire through and not enough to feed a joined wire through. It would have been expensive to start cutting the wall board to get to where I needed to drill. I purchased 3 of these common makers and they worked flawlessly, even the one that is the other side of the house. Very simple to wire, lots of different wiring options depending on your system. I now have 5 Ecobee Smart Thermostats hooked up replacing the 20 year old ones. Worth every penny just in not having the stress of feeding wire where it would need a professional.

My electrician installed it for me in my apartment I own it stopped working within a couple of days my tenants called with no heat. My electrician came and removed it. The unit in the wall attached to the thermostat was very warm my electrician told me to get rid of it and we will run a 3 wire instead.