How HVAC Wiring Works - How To Install a Nest Thermostat - New Google Nest vs 3rd Gen

In this video I take you through the detailed process of replacing a thermostat with the Google Nest 3rd Generation. I also demonstrate the process of finding the thermostat wiring and possible issues to watch out for.

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Blessings,

Ben

[rogerbarrios]

I’m not even working on any HVAC project….and I found it very interesting. Thanks for all the hard work producing it. Great job.

[Balasubbarayan]

The best and most helpful video on Nest ever. Was struggling with the wiring between the furnace, air handler and Nest. This video nailed all the ambiguities to the point. Thanks much!

[comingtofull-ageinchrist]

I was going to ask why the red wire from the outside unit was tied into the red, but then I realized it was just supplying 24 volts to the cooling. this was a really great video. I've impressed with your knowledge on all these different systems from older to newer. Great job, Ben!

[grandmasterwade]

Thank you for such an explaining what the color wires mean! None of the other videos showing up first did that.Helped very much for my installation.

[PapaGleb]

Amazing video Benjamin. So detailed and clear, thank you. I just moved into a 90 yr old home and have been slowly modernizing it. Replacing the mercury thermostat is next which is how I found your video. My system is heating only so I only have 2 wires to work with. Trying to avoid any extra work so Ill probably go with the Nest E which will already be a huge upgrade from the mercury one I have now but again thank you for this detailed video. Ill be down at the basement today checking out the furnace wiring.

[eddiekester]

Nest has two very nice features -
1 - it can obtain as many as 6 skips across a lake if you sling it just right
2 - Wrapped in electrical tape it makes a great street hockey puck

[juanrrobledo]

Great job explaining the step by step, my son bought the Nest Thermostat with the mirror face, I’m going to set it up and wondered about the jumper wire and you explained it perfectly

[AllenCavedo]

Excellent video as always.

I have a Nest 1st gen and a 3rd gen in same house. I liked Nest better when Nest was Nest and not Google. I think Nest has several design problems but the worst one and so easy to fix but they seem oblivious to the problem is when you turn the dial on the wall or in the app, it INSTANTLY heats or cools. There should be a 5 second delay before accepting the temperature change. This because it is easy to make a mistake and overshoot your intended temperature setting, especially using the app.

[morlamweb]

When I first installed my Nest 3rd gen, I had just the R/W/Y/G wires in the wall, and the Nest would regularly run out of power every few days. That was an annoyance in summer, when we could instead run some fans and open some windows, but it's dangerous to have that happen in winter. I knew that it was connected to the air handler in the attic, and that it had a 5-wire cable running to the t-stat. So I fished the cable out the wall, and sure enough, there was the C wire wrapped around the cable. I plugged it in to the plate for the Nest and solved the battery-discharge problem. Later, when I installed the Nest e (low-price version of the 3rd gen) for the first floor heat, I made sure to run a new 2-wire cable from the base to the wall, connected it to a 24V source at the boiler, and to the C connector on the Nest. I've had no problems with it since installation.

[judyfleming]

Thanks! We need a new thermostat. I will definitely be showing this to my husband

[TheTerminator-nj]

I haven't seen a thermostat like that since I was a kid. 💯

[dapperdave]

nice haircut... 👍😎👍 I had to pull in another wire (ground or common) to hook up and power up the new thermostat

[DavidMcCurley]

I like the haircut. Also great video. Super informative.

[olbaid]

Thank you for this video. I’ve been trying to figure out how my thermostat was wired (same one as yours), and the RH wire kept throwing me off because mine was tied into R at the furnace just like this one. Amazing!

[bobniles]

I like the high and tight. Leroy Jethro Gibbs would be proud of you.

[raynalreyes]

Wow as a designer I never noticed the similarities between the two devices, I've used the honeywell in a bunch of places and outside in the world but great job with the video! I think since this may be people coming in to look at the info and then bounce, it'd be good if you come up with a good way to tell people to subscribe, etc... so that it makes you different from your videos... just a constructive thought! good job again with the video, audio and video are 10/10!

[comingtofull-ageinchrist]

WD-40 makes a lubricant for tools that supposed to protect them for a year. I've used it on some of my hand tools that were exposed to excess moisture, and laid them on a rag and sprayed them heavily and just let them soak for about 30 minutes and wiped them down. You'll be surprised with the outcome! I found some at Lowe's near me, but I'm sure other places like Home Depot and Ace Hardware probably carry it as well. they used to sell some stuff in a small bottle that you could put on rust and it would kill or convert it. I bought some from Home Depot and used it on some shovels back in the late 90's, so I'm not sure it they carry it still. Home Depot carries some Rust Oleum that has good reviews. It would probably make your Knipes needle-nose look new again from reading the reviews! it's 68 dollars for a 32oz. bottle.

[michaeljavert]

Thank you for posting this. I am going almost exactly the opposite direction. I went out of my way, and way out of my budget, to get a thermostat similar to the one you removed, from The E-Bay. The older, in my experience, is more reliable and precise. True, I can't control it with a smart phone, and the government, company, and utility company can't collect data, build their dossier, and sell it to brokers, which is a good thing. I can get out of my chair and walk to the thermostat and twist a dial until I am comfortable. (If I can afford it. But that's a different story.)

The thermostat I am installing has terminals for BGORW, which I assume are blue, green, orange, red, white. but the thermostat I am replacing only uses 4 wires, then it splices into a mess in the basement at a few different points. Probably going to have to get someone out here anyway. I have 7 wires total, 4 at thermostat, 3 are not used, to a rats nest in the basement in 2 different places. Hope it works using what I have.

[rodolfosiles]

Best explanation on how to replace and old Honeywell thermostat!

[TVJAY]

I would love to see a video on two stage heating/cooling.