Install Amazon Smart Thermostat + C-Wire (less than 4 minutes!) 

You can avoid purchasing the adapter if you have unused wires in the main bundle of wire coming out of the wall. With my thermostat I did not have a C wire designated but I did have 4 unused colored wires in the bundle that were tucked back into the wall. Pick one of the wires to become the C wire. I chose the blue wire as it is the most common choice for C. Now turn your power off to your furnance and open the side panel. Look at your motherboard and you will see all the connection screws that are the same as the thermostat such as W,Y,G, R, RC ..etc. There should be a C terminal as well. In my case, I had a red wire already connected to the board C terminal that was connected to R and RC at the thermostat. It does not matter as the new wire will also be connected to the C terminal. Find the wire bundle coming from the thermostat into the furnace. You will see some of the wires already connected to the board and some that are not connected to anything. In my case, I stripped the blue wire that was unused and connected it to the C terminal. It does not matter if there is already another wire connected to C. That is it. You now have a blue C wire and do not need to pay for the adapter or use batteries to keep power to the thermostat. The other colors that were connected to my old thermostat such as G,Y,W,R,RC were connected the same terminals on the Amazon thermostat.

Thank you very much, your clear explanation was life saver for me. Even though it took more than one hour for me going through whole process, this journey was really enjoy for me. Especially, my daughter liked your “why? I don’t know~” part and repeated tones of times. 😅

Thanks Matt 4 minutes of wisdom, every step lead me to make an installation painlessly. Even removing the cover of the burner

@2:58 the G->C and Y->K was the lifesaver for me. Couldn't figure out what was going wrong on the thermostat side, thought I had everything labeled right. But that little swap is what did it for me. Thank you for the great informative video.

Thank you so much for this video! I had one hell of a time installing my new thermostat and your video is the only one I found that actually helped. Appreciate it man!

You shouldn’t have to open the air handler. I have a heat pump and connected all the wire EXCEPT I had to connect the white wire to W2 and the orange to o/b…if your system blows hot air when ac is on then you go into settings and switch O to B or B to O

The little blue tab on the thermostat needs to be on the up position that blue tab is actually a jumper so you have an extra wire remaining also

So at 2:17 does that c wire adapter wire need to be connected to the smart Alexa thermostat or is that c wire adapter a substitute and a wifi substitute?

My existing thermostat only has red, blue, and white connected. The yellow and green wires are there, but not connected to the existing thermostat. Should I connect these to my amazon thermostat?

Wow thank you so much for this video

this is great and probably works in 90% of applications, but here in the northeast, we have gas boilers and baseboard heat which means no control board at the boiler(instead we have an Aquastat). In my application, the smart thermostat will be controlling both the heat and the AC (R1&C used). I have extra wires (3) coming to the thermostat and a 24v transformer near by boiler, the question is where to connect the 24v to the device?

I don't have a yellow wire going to Y it's a blue wire. So could I still have a c wire cable if the blue is connected to Y?

I have an older thermostat and only 2 maybe 3 wires come out the wall.. would this be a problem?

Excellent video. Saved me a lot of time. Thanks!

Thank you so much for making this video. It was a lifesaver for me. Followed Alexa’s step by step with no success until I watched this video!!

on alexa app, i dont get the "amazon" brand listed after clicking thermostat device? do you know why?

Where did you purchase the c wire?

How could I not trust a fellow metal square G owner! Cheers

Does the adapter work without a blue wire?

I only have 4 wires on my old thermostat. Green, blue, white and red. What do i do?

Thank you for this video it helped tremendously

Fun edit style !

if you have two thermostats do you need two c wire adapters?

Did you use a Honeywell C adapter for an Amazon smart thermostat?

My thermostat only has a RC RH and a W wire. What am I supposed to do? Also when you went to the basement and open-end up the furnace you totally lost me. No clue what you were talking about there.

I did all of this it connected successfully everything seems fine but my furnace won’t turn on now.

What is I don't have a yellow? And the blue was in y?

Wait on the adapter we just terminate blue with blue??

Do you lose the option to turn on your fan by using this method?

Great video!

i did exactly this and now i have no heat setting just ac

Which port do we put the blue wire in, I been in this one for a long time

Great work ! You're a pro!

What if i dont have a yellow cable then what

How do I know if I need C wire?

You can’t set the fan from constant to automatic from your phone that was very disappointing for me a dealbreaker.

925 Micaela Creek

The screen doesn’t show anything and the ac wont come on now what’s up?

So blue goes where

Jared Overpass

Ruecker Streets

Powering up a return wire is never good for any equipment. If someone did that with high voltage AC, you could kill someone on the line. Proper procedure is replacing any 18/4 with professionally rated 18/5 that is NEC rated for temperature / fire and has a valid PVC jacket.

Replay Time! :)

Could have just flipped the switch to turn off power 😂

You seriously need to redo this video. Get rid of the 4 minute limit and do it correctly.

Several of my wires are not colored or arranged like this. Several connections have 2 wires on them. This smart thermostat is more trouble than it is worth. Have to hire a professional to install the C adapter to avoid blowing up my system or killing myself. Such a stupid product.

Video is less than 4 mins. But actual process will take much more 😡

4 minutes huh ?

No way. That's doing too much.

4 minutes? 😂😂😂

29326 Dan Creek

my wall only has WGR. is that a problem?