How to Install a Nest Thermostat with Only Two Wires

[@Bootstrappin]

New Nest video: how to install with HVAC system kzbin.info/www/bejne/nKCUgX2Vjamaick If your furnace isn't supplying power to your Nest with two wires, you have a few options 1) Google Nest Power Connector - Nest Thermostat C Wire if your furnace isn't supplying power to your Nest: amzn.to/3tcWwzq 2) Adapter, run this as a "C-wire" to your Nest: amzn.to/3qvVTOu Nest 3rd gen: amzn.to/3G7mKYf More energy saving how-to videos from me: kzbin.info/www/bejne/l6CcmoKei62pjdk I'm an Amazon Affiliate, and earn commissions if you purchase through these links at no extra cost to you. It's a great way to support the channel, and it is much appreciated!

[@Gordon013]

Just wondering if your nest Thermostat makes a ticking or buzzing sound when the signal is being sent to turn the heat on? I had the same setup, and since the thermostat was trying to use the signal wire as the common at the same time as sending a signal down to turn on the furnace it would get a ticking or buzzing sound. I solved the issue by adding a common wire so it had a dedicated line to complete the circuit to the thermostat to maintain optimal power. luckily for me I only have to run the third common wire a short distance so it was not an issue.

[@RayShellz]

@@Gordon013 man... you're a life saver... same exact thing happened to me... I installed it about 3 weeks ago... when it wasn't super cold... so the furnace worked and everything but the burners didn't and it was just blowing cold air... but I couldn't tell that until the temperature got below 32°... so I seen your comment and just ran a 4-wire and just used 3 and now it works like a well oiled machine👍👍👍 thanks brother

[@MrDanyeloy]

Ray Shellz you forgot the first plate cover

[@RayShellz]

@@MrDanyeloy what's the first plate cover?

[@jacoblopez1446]

I do wanna use a nest termostat but the wires on the old termostat is 110v can I used to install the nest or not thank you

[@stephenbennett7176]

36 years in the industry and it’s so nice to see someone with a great sense of humour . Keep it up 👍🏼

[@cezheng8624]

he is just very emotional and dramatic

[@NathanMichaelBlack]

I bought my nest thermostat about a month ago but was too anxious about screwing up the install, so it just sat on the shelf. Your video helped get it done. Thank you! It's so amazing and it was so easy. I also added sensors in the basement, a bedroom, and the attic so I can see all the temps in the house. So cool.

[@Bootstrappin]

Glad it's working!

[@PressuredSpeechBand]

The commentary is the best part of this video! Love the enthusiasm!

[@pinkpeony5871]

Thank you! Just the video that I needed. I only saw two wires and was completely confused by other videos showing 4 colored wires. I'm going to do this myself and you can take all of the credit!!!

[@donchulo83]

Did you need to add a common wire to keep it charge?

[@pinkpeony5871]

@@donchulo83 Don, when I hooked it up with he two wires, that's all it needed to stay charged. It's electric.

[@deuswulf6193]

@@pinkpeony5871 Real pros can get it to work with no wires.

[@pinkpeony5871]

@@deuswulf6193 Well, I'm not a pro! lol.

[@sayid160]

@@pinkpeony5871 is it still working properly with 2 wires?

[@RogerDiotte]

So today I installed a Nest E thermostat into a Heat Only system that had 2 wires. I need the C-Wire power because of troubles in the past with other setups where it worked for awhile and then didn't work shooting the error no power on R wire. Anyways, in my setup I luckily had more wires tucked behind in the wall so I went to the furnace and found that the C-Wire (Blue Wire) wasn't attached so I attached it and now I have the Blue Wire connected to the C terminal on the thermostat and problem solved. If your lucky you won't have to deal with ordering the 2 wire Venstar kit off Amazon which again I had to do on another setup I recently did and the Venstar fixed that issue in a jiffy!

[@stellahsgroove]

Youre amaxing! Customer service told me my system wasnt compatible...but bc of you..it works nicely! Thanks!

[@Slayerz0159]

nests are nice, I like them. some systems require a common (C) wire to power the nest. its just 24v to charge the internal 100mah(i think) battery. red wire and white wire are your wires for heat which is W and RH. if your furnace has w1 and w2 its a 2 stage furnace. high and low. same with cooling y1 and y2 for a 2 stage AC. green wire is for fan only. O(orange) B (blue) Rc (red) all can control a heat pump/geothermal. Orange is the reversing valve for the heating or cooling portion of the heat pump. Blue is the common 24v for the heat pump. and Rc is the power from the heat pump. remember! this is all just copper wire. someone may have arranged the wire colors differently on your units! so check the board in your furnace/ heat pump/ ac before assuming they are correct. ive met many color blind co-workers!

[@jphatala]

Hello and thanks for the video. I too have a 2 wire boiler and hooked up the nest as you suggested. However, I continue to get an error stating that there is no power to charge the battery. I obviously don't have a c wire, any suggestions?

[@Bootstrappin]

Few things. Try swapping Rh with W1. Also, make sure that you strip about 1/2" of wire jacket and make sure it's really jammed in there. If that doesn't work, take a multimeter, turn it to 'AC' and measure voltage between the two wires. It should read 24VAC, roughly. If it's not anywhere close, you might need to add a common maker kit either to the furnace, or use a wall plug.

[@TheMiano1]

I just bought the white Google Nest (not the "Learning" model).. the wiring board has three spots on each side. One is Y, C, W and the other is G, R, OB. How would you wire 2 wires in this? (I have white and black wires for heat-only

[@venusfan]

Mine ended up needing the C wire so I just bought a plugged in 24V adapter and run it behind the wall along the door molding to an outlet.

[@mrpreston8230]

Which terminals did you plug the adapter into?

[@njtoyjunkies366]

????

[@greysign]

Is it ok to turn off the burner even though it says for emergency use only? For some reason the breaker labeled “furnace” to my house is not turning the furnace off. And when you switch the burner off, I’m assuming it cuts power to all the thermostats in your home as well? Also, once done, and you switch the burner back on, any problems? Thanks.

[@Bootstrappin]

Yes, that is what that switch is for. Should in theory also cut power to the thermostat. Would be good to double check and make sure that you can't turn the furnace on with that switch off. The only problem I could foresee is if you have a gas furnace that has a manual pilot light -- you may have to relight it yourself if that's the case.

[@greysign]

@@Bootstrappin Thanks for the reply.

[@ehabsabha3620]

I had the 220 Volts system and had to buy transformer and did interface with relay to do it and it worked 💪 But forget about two wires , it does not work as your nest had to charge and it will not charge without the C wire, keep taking it out and charge it like your mobile is not practical 😉

[@navrajthiarajatt]

Which transformer did you buy? And how did you add C wire to the transformer?

[@TallCoolOne5378]

Liked because the cutie Kitty 🐈.at the end of this video..lol.. And yes...the video was both entertaining and informative .you rock!..😉😎.

[@aeidher]

Thanks for the video. I tried this with a old school 2 wire thermo connected to a fireplace. It didn't work, the Nest didn't power up. Any suggestions? Thank you

[@Bootstrappin]

Basically your two options are: wire the Nest C-wire adapter into your furnace (it comes with instructions - link below), or you get a wall adapter. All you do is plug it into a nearby outlet, and it provides you an extra wire to run into the back of your Nest: 1) Google Nest Power Connector - Nest Thermostat C Wire if your furnace isn't supplying power to your Nest: amzn.to/3tcWwzq 2) Adapter, run this as a "C-wire" to your Nest: amzn.to/3qvVTOu

[@aeidher]

@@Bootstrappin thank you. That's exactly what it was, not enough power. I did give it a charge with the mini USB, reattached it and found it wasn't getting enough juice (via the UI). I will look into your suggestions, thank you.

[@albertsantiago6305]

Thanks you made this very easy to install thermostat Nest thanks for your help 👍

[@Bootstrappin]

@@albertsantiago6305 sure thing!

[@jaimeperez5572]

Hilarious yet instructive. Great job sir. 👏👏👏

[@Bootstrappin]

Thank you!

[@raywest3834]

Poor guy puts out a helpful and entertaining little video, then spends the rest of his life answering questions about it!

[@Bootstrappin]

As funny as it is true lol

[@malteeaser101]

And those two wires go to T1 and T2 of the Heat Link?

[@booradley1065]

If you have a millivolt thermostat this won't work . Another video shows how to do it by adding a 24v ac adapter to power the nest. pretty cool.

[@pattayperformance]

I can’t install the Nest Thermostat in my parents old home. It is two wires black and white. Wires are too thick (like an outlet) and won’t fit in the thermostat) Do you know the fix?

[@honainmushtaq9527]

@@pattayperformanceyou can just use thinner wire to connect them

[@RahmanRezky]

Thanks for sharing your experience with Nest. I'm thinking of buying one for my apartment, for cooling system. With only two wires, is it possible to control the fan as well?

[@jimwang6165]

I have the question

[@CLAWZGALAW]

The excitement over the included screwdriver tho 🤣🤣🤣

[@casedinlemn3961]

the guy was sponsored to do this ad. i hope so. otherwise, you're pretty dumb to pay 300 for it and have an orgasm for a 1 dollar screwdriver. wtf

[@leftover7766]

That little tid bit saved me from getting out of bed.

[@Bootstrappin]

That's patently false. I paid for this thing with my own money and have no affiliation with Nest. I do get overly excited about nifty touches though, guilty as charged.

[@riggamawesome1]

very helpful and specific to what i was looking for ty

[@mackiemctyson5085]

It does die eventually as it doesn't get a constant charge from lack of not having a C wire. Some folks are ok though with just pulling the nest from the wall and charging as needed.

[@joseprado1972]

Awesome video just installed mine last night thanks for the video.

[@Bootstrappin]

I'm happy I could help!

[@jonathanearl2255]

How’s the battery life?

[@NyxT-GyreX]

@@Bootstrappin hey man how are you? How is the thermostat so far since I might have the same HVAC system do you ever needed a c wire?

[@Bootstrappin]

@@NyxT-GyreX I moved out of that house since then. But it was fine -- ran for about 2 years without a C-wire... but your mileage may vary.

[@NyxT-GyreX]

@@Bootstrappin oh so you had to install a c wire by then? 🤔 thanks for you reply

[@clu8688]

Hey bootstrappin! Great video but question, I have an only heater/radiator system as with the same honeywell thermostat but the wires on mine are green and blue without any labels. Is it 24v and can I also just plug either of them in W1 and Rh?

[@Bootstrappin]

Thank you -- if you're not sure, a good way to find out is to take a multimeter, set it on AC voltage, and check what it is. It's tempting for me to say "it's probably fine", but I've seen too many questionable electrical things in homes that it's better to double check.

[@theunit5939]

Have you had any issues with the 2 wire set up at all, has been giving you any issues with no c connected?, great video thumbs up...

[@Bootstrappin]

I had this setup for a couple of years and I never had an issue. I'm hearing an occasional rumbling/rumor that Nest, through a software update, disabled the two wire configuration? I haven't confirmed this and unfortunately can't check because I've since moved out of the house.

[@SmokeTubeBBQ]

i have the two wire setup for just heat...works great

[@zachary040619]

@@SmokeTubeBBQ this is the gen 3 Learning thermostat correct? I settle on a home April 6th and have been eyeing the old thermostat with mercury tube on the wall since I first stepped foot inside. I have one in the dining room for radiator heat and another upstairs that controls the A/C. I'm going to buy two gen 3 Learning thermostats but I assume the really old thermostat only has two wires....any problems with yours thus far?

[@AnthraXaXis]

dang you sold me.. and made me certain it'll work in my house! cheers 😊👍🏽

[@Bootstrappin]

Right on!

[@K1KO247]

Question. I have a 2 wire set up also. The nest is hooked up on an old thermostat with just 2 wires to my Noritz tankless heater. However my nest isn’t charging through the base i have to remove it from the wall and charge it via usb do you have that same issue???

[@Bootstrappin]

I do not, mine charges through the two wires. It may not have enough current or runs on different voltage. Take a multimeter, set it to AC, and take a measurement on the two wires, it should be 24VAC to charge the Nest. Some setups may require a third common wire unfortunately.

[@GusgusA1]

Thank you, I just did it. No fire 👌

[@Bootstrappin]

Outstanding! Nice Square btw. K5?

[@GusgusA1]

@@Bootstrappin k10

[@kcarroll5061]

Does this work with a gas furnace. We are replacing the exact same thermostat. Thank you.

[@Bootstrappin]

It worked for my oil furnace, but your mileage may vary. It all depends if the circuit board of your furnace can supply enough current, and if it runs on 24 volts AC. You may need this if it doesn't work: amzn.to/3tcWwzq

[@nickpanhead7209]

Great video and very informative, but funny. I picked up a used nest 3 gen, for a furnace i put into my garage. I wired it up the same as yours 2 wire setup, all good. But i guess the way the old owner had it wired, it came up. The wiring to your equipment has changed. And at the bottom of that in blue it said continue. I dont have a manual for it. And im not fully set up with the furnace neither. So i didnt go any further, what im looking to do, is install app in my phone eventually. And only use it to turn on heat in garage while im having a cup of coffee in the house and go out a half hour later to a toasty garage. Is there a way to do that. Im assuming the wiring change thing will walk me through it once i hit continue. Just want to turn on when i want, dont want it to come on its own when temperature drops. Is there a way to do that you know. Thank you

[@Bootstrappin]

Ah yeah, it'll probably walk you through all the same. But part 3 of this website has the factory reset procedure, might be good to go through: www.techsolutions.support.com/how-to/how-to-factory-reset-your-nest-smart-thermostat-10113#:~:text=3%20Nest%20Smart%20Thermostat%3A%20Factory,Settings%20and%20press%20to%20select. As for leaving the garage for getting toasty, that's an interesting pickle. Certainly you could just set it or set the temperature from your phone app. It does have geo fencing which detects when you leave your wifi network and you can set it up to have whatever behavior you like upon leaving... But easiest is probably just from your phone.

[@nickpanhead7209]

@@Bootstrappin thank you for getting back to me, I will definitely check out what you said. Im still getting things together for furnace, hopefully when the winter comes I'm up and running. Thank you

[@Blah-blah-sure]

Thanks so much for your enthusiastic video. I also have a 2 wire that had a Honeywell C67N. But was told i could use the Nest thermostat? So whats the story? Because i was going to hook mine up like yours. And yes, im aware of the usually Thicker gauge house wiring. In which the one's for my thermostat are the thin wires

[@Bootstrappin]

Hard to say, I could only find info on the CM67. If it's the CM67 that you have, then it looks like a Thermostat for European markets, considering that I see 230 VAC on its spec sheet, though it also seems to be compatible with 24 volt systems. If you have a multimeter, I would check to see what is running on that thermostat. Thicker wires can be a decent warning sign that it's 230 VAC, but not always guaranteed, so it's good to check. If you're certain that it's a 24 volt system, then you could try the Nest. Otherwise, the Nest 3rd gen would NOT be compatible. thermostat.guide/honeywell/honeywell-cm67-programmable-thermostat-product-specification-guide/

[@alanbarr8301]

great video. thank you for the instruction. I have a bit of a different scenario that is a head scratcher, we are installing new cooling units (Samsung 360 Cassette 46,000 btu model), but we do not have any heating whatsoever as we are in a very warm location year round. The samsung thermostats (model MWR-WE13N) have a low voltage 2 wire connection (labeled F3 and F4) , similar to the 2 wire heat that you just demonstrated. I've tried discuss this with Google nest support and they have been useless. We are looking for a diagram, and advice, whether 2 wire with Samsung products, can be set up on Nest Learning Thermostats. We are also more that happy to add control wire separately to power the thermostat so that isn't the issue here. Any advice? Cheers!

[@Bootstrappin]

Bit of an educated guess on my part. I read your Samsung thermostat's manual, and it sounds to me like the F3/F4 cable is using a communication protocol, while also supplying a bit of power. The protocol is key because it looks like you can control many things over two wires - cooling, fan, power, maybe even heat if you had it. Nest operates on relays - it has a unique pin for every function. My new HVAC has a dedicated wire each for cooling, heating, common, 24V, and fan. So at this quick glance, I feel like it wouldn't work with Nest.

[@Bootstrappin]

So if I'm right about the protocol, which seems to be RS-485 (another guess), you could make it work with an adapter like this (again, perform your due diligence, this is just a quick and dirty answer) www.komachine.com/en/companies/cyclogic/products/76974-CL-IM08A

[@Avalanche2]

Wont the internal battery die without the 24v to keep it charged?

[@Bootstrappin]

That depends if the circuit board from your boiler can supply enough current. In my case, I was able to run the thermostat with this exact 2 wire setup for years without problems.

[@christinez-z786]

When you set the temperature to 60F in hot summer, will it give you cool air because of the Nest Thermostat?

[@Bootstrappin]

Only if you have an air conditioner or a fan as part of your system

[@christinez-z786]

@@Bootstrappin Understood. Thanks for responding so fast!

[@ravishankard5937]

I am trying to upgrade my current Honeywell HVAC system with EIM to Nest (3rd Gen)... In my existing thermostat (Model: THX9421R5021WW), I only have 2 wires coming into my thermostat (White and Red) but it controls both Heating and Cooling using the EIM. Can I use the above recommended approach for my upgrade? i.e will it work?

[@superz20]

if i turn off all the breakers it should be fine as well right? i was told never to touch that on/off switch cause its an emergency switch off

[@Bootstrappin]

I don't see what a circuit breaker would accomplish that's different from an emergency switch. But yeah, if you find the right breaker, it should accomplish the same thing.

[@Br3ttBork3r]

Did you have to find out what voltage the wires were? Mine is similar very old system and has 2 wires, white and black. The circuit board says 120v though. I’m very confused. Do I need to convert the system to 24v, does any of it matter?

[@Bootstrappin]

It does matter, very important! With mine I was confident about 24V because the wires were very thin, and I measured them with my voltmeter. Measure the voltage across your wires (you may have to have the furnace on for this). If it's 120VAC, the Nest is *not* compatible. There are probably ways to convert from 120VAC to 24VAC, but I don't honestly know. Tread with caution, 120VAC is enough to be lethal.

[@sromero1160]

If I have a 120/240v old thermo do I need to install a transformer to lower the voltage still ?

[@Bootstrappin]

Not sure about that one. Just guessing here, but on the surface it sounds quite painful, step down to 24VAC for Nest then step back up to 120VAC again to maintain compatibility with your furnace. Probably easier to just get a 120VAC thermostat.

[@sromero1160]

I am asking I want to switch to a nest and from what I read, it says that it wont work if my thermo is running at 120/220 . I don't wanna buy one and not work lol

[@nelseify]

If you buy this in the uk/Eu it comes with an extra box called a heatlink to handle the high voltage switching of the boiler. Do not try to work this with a 240v system without the heatlink

[@Bootstrappin]

@@nelseify also keep in mind the EU uses 50 Hz instead of 60 Hz for AC electricity. Might still not be compatible here.

[@lenny0272]

Back Plate...good video

[@kingjean]

Soooo can the 2 wire be used for cooling as well I have a gas furnace

[@Bootstrappin]

No, cooling usually requires at least a fan wire, an air conditioner wire, and a common wire. If you have heating and cooling, you probably have at least 5 wires.

[@patf3207]

I also only have 2 wires, but one was wired to R and the other was wired to C? Should I assume that this was not supposed to go to C? Or should I put it in C on the knew one?

[@jimp4878]

Any idea which Nest Model this is?

[@Bootstrappin]

Generation 3

[@jimp4878]

@@Bootstrappin Thanks

[@alicialehoux4796]

My old house has two wires thermostat too. They are black and white. I am wondering if they are AC or DC?

[@Bootstrappin]

Generally speaking, they will be 24 volts AC, depending on your furnace. Only in rare situations do furnaces use high voltage AC. To know for sure, take a multimeter and probe the wires in both AC and DC mode.

[@rickw4160]

they are both ac, but old systems can be run on 120v. newer ones are usually 24v. you can buy a transformer at home Depot that will convert it.

[@superz20]

love the commentary !

[@maleeabbas]

I only have the RH and W wire as well. I want to install the Nest but installation video persists on getting a C wire.. Any suggestions?

[@Bootstrappin]

Installation video on their website? Have you tried powering on the unit without a C-wire? If you have and nothing happens, see my pinned comment, I'll paste it here: If your furnace isn't supplying power to your Nest with two wires, you have a few options 1) Google Nest Power Connector - Nest Thermostat C Wire if your furnace isn't supplying power to your Nest: amzn.to/3tcWwzq 2) Adapter, run this as a "C-wire" to your Nest: amzn.to/3qvVTOu

[@maleeabbas]

​@@Bootstrappin #2 adapter will be my way to go ... My only dilemma is the new nest i got has slots of W, G, R, W, Y, C, & OB* wires ... My original thermostat has wires going to W and RH.. As this is heat only thermostat. With the adapter, could you guide which wire should go in which slot? I am guessing W to W, RH to R.. But what about the two adapter wires? One goes to C, other would go where?

[@Bootstrappin]

​@@maleeabbas This is the diagram they provide on the listing, is there anything missing from yours? m.media-amazon.com/images/I/71Qkv2KPlaL._AC_SL1500_.jpg

[@RAMBOLOGY]

I tried this but it wasn't working out. Had to trace the two wires back further and discovered it was being muxed. 5 input wires into a circuit board and then output of two wires to my old thermostat. I actually had all the wires needed to hook up the nest properly. Felt like a winner and an idiot for not catching it sooner at the same time.

[@Bootstrappin]

I'm glad it worked out, sounds like you had some MacGyvering to do!

[@maincreep]

At the end of the video you mention the 2 thick wires with higher voltage...whats the process for hooking up to those?

[@Bootstrappin]

If you have high voltage wires, you'll need a specialized thermostat, Nest isn't compatible as far as I know. It's probably possible to cheese it with a relay though. This guy goes into some detail: kzbin.info/www/bejne/aZ6QeIiVYpx6jZo

[@maincreep]

@@Bootstrappin thank you for the reply, I will check it out.

[@taika2]

just came across your video i was all day trying to connect with 3 wires from my old honeywell just like yours but i have a green,black and red wire where do i connect to. i thought green wire for G , B for blackwire and the RH for red wire but it didnt work. the nest read i had no cooling or heat connected?

[@Rony718]

I have high voltage 120 volt. The thick wires wont even get in. Which transformers would I need?

[@Bootstrappin]

The Nest does NOT support 120VAC and if you went so far as to attempt to poke 120 volt wires into the Nest, you should call a professional before you get hurt. 120VAC is dangerous and can kill you. That said, call Nest, I'm sure they have a solution, and peruse this thread, a transformer/relay is mentioned: www.doityourself.com/forum/thermostatic-controls/541504-thermostat-conversion-120

[@trabelsiachraf2361]

RC840T240 RELAY WITH TRANSFO 208/240V Brand: OUELLET Mfg Number: RC840T-240 Rexel Part Number: OUERC840T240

[@samarafriedman3857]

Thanks for the video! This worked like a charm.

[@Bootstrappin]

You're welcome! Glad I could help.

[@midiman5045]

Yours is the E Learning on am I correct? What Gen? Are you having issues with your batteries charging?

[@Bootstrappin]

No -- I had the 3rd gen, and it ran fine that way for a couple of years before I moved out. I think it's just a matter of if your furnace circuit can supply enough current or not, and that's a bit of a toss up. amzn.to/3G7mKYf

[@midiman5045]

@@Bootstrappin Thanks for the reply. you had the Learning one. Mine is 24 volt 20 years old. I hope it will work.

[@georgebrodie9795]

Have you had any issues with your nest not working right because of the two connection

[@Bootstrappin]

No, but sometimes the furnace can't supply enough current through two wires. If that happens, read my pinned comment - you may need to make a common wire.

[@georgebrodie9795]

@@Bootstrappin where would your pinned comment be

[@georgebrodie9795]

How do I go about making my c connection

[@Bootstrappin]

@@georgebrodie9795 ordinarily, it should appear at the top of the comments. Either way, I'll put it here too, but basically your two options are: wire the Nest C-wire adapter into your furnace (it comes with instructions), or you get a wall adapter. All you do is plug it into a nearby outlet, and it provides you an extra wire to run into the back of your Nest: New Nest video: how to install with HVAC system kzbin.info/www/bejne/nKCUgX2Vjamaick If your furnace isn't supplying power to your Nest with two wires, you have a few options 1) Google Nest Power Connector - Nest Thermostat C Wire if your furnace isn't supplying power to your Nest: amzn.to/3tcWwzq 2) Adapter, run this as a "C-wire" to your Nest: amzn.to/3qvVTOu More energy saving how-to videos from me: kzbin.info/www/bejne/l6CcmoKei62pjdk Nest 3rd gen: amzn.to/3G7mKYf

[@georgebrodie9795]

@@Bootstrappin thanks for all your help

[@mhuck11]

Will this work with all Nest thermostats? The one I have is the Nest Thermostat

[@Bootstrappin]

It should - but that largely depends on whether your boiler circuit can supply enough current to power the Nest. That's a gamble, but you can always install a common wire after.

[@TaddyMason74]

what features aren't available when using the two wire setup?

[@Bootstrappin]

None I can think of. Typically it'll control an entire HVAC, turning AC on/off, maybe the fan. Either way, full features.

[@furnacetech2581]

R (ed) - Power Y (ellow) - Cooling W (hite) - Heating G (reen) - Fan C - Common R + Y = Cooling Only R + W = Heating Only

[@ted3bare]

Nice video but how did you determine to put the black wire to W1 and the white wire to RH?

[@Bootstrappin]

It didn't matter for me, worked either way.

[@terrywood8519]

What model Nest did you use?

[@Bootstrappin]

Nest Gen 3, link below amzn.to/2RZmPnq

[@terrywood8519]

TY

[@stu101]

Did you still need to wire the receiver unit to your boiler?

[@Know-Tree]

will it work on my base board heater which has only two wire ?

[@Bootstrappin]

Only one way to find out! You may or may not need a 'C' wire adapter.

[@Know-Tree]

@@Bootstrappin Thanks for your prompt reply

[@BlackSmith222]

My old honeywell thermostat has 2 wires. When I try install nest 2020 (not nest learning). Setup asks for C wire required.

[@Bootstrappin]

Interesting, I guess it doesn't always work. I have a link to a C-wire adapter and a common maker in the pinned link.

[@BlackSmith222]

@@Bootstrappin Since my heating has 2 wires Red and White only. So for a C wire. I plan to use transformer option. My nest 2020 has Y, C, W, OB, G, R, terminals. From transformer 1 wire goes to C, which terminal the other wire goes?

[@Bootstrappin]

LegoBanda like this: images.app.goo.gl/Q1tajPeo7RpWEomD7

[@hollywoodjack]

do you need one thermostat like that by zone?

[@Bootstrappin]

Yes, seems that way

[@autracing82]

what model is that google nest the mount is different on the one i have

[@Bootstrappin]

Nest Gen 3

[@ceco911]

I have an old 2 wire low voltage setup and want to switch to a Nest. Which Nest model did you use? I've seen a few videos with people using the "E" model with 2 wire. Just trying to get as much info as possible before I order a model. Thanks

[@Bootstrappin]

This is the Nest 3rd Generation, but it should work with 'E' model and 4th generation as well. store.nest.com/product/thermostat/T3007ES

[@ceco911]

@@Bootstrappin Awesome, thanks for your help.

[@devin7822]

What do you do if it wants a common

[@Bootstrappin]

If your furnace isn't supplying power to your Nest with two wires, you have a few options 1) Google Nest Power Connector - Nest Thermostat C Wire if your furnace isn't supplying power to your Nest: amzn.to/3tcWwzq 2) Adapter, run this as a "C-wire" to your Nest: amzn.to/3qvVTOu

[@shortyyboox]

I have a R wire and W wire only. I don’t see a sign for high voltage either. Will this video work for mine??? Thank you!! Hope to hear from you.

[@Bootstrappin]

Sounds like you have a heater only set up. Yes, sounds like it should work: turn off your boiler by hitting the "emergency off" button, put 'R' to 'Rh', and 'W' to 'W1', then turn your boiler back on and you should be in business.

[@shortyyboox]

You are awesome!!! Thank you!!!! Will Let you know how it goes!

[@mehnaaz118]

Hi

[@mehnaaz118]

I have a green n red wire only plz help me to put my nest thx

[@WA-hornet007]

Near needs direct source of power to keep it charged , I did not see you connecting a wire for power or did you ?

[@conorko]

Great vid man, absolutely luv the enthusiasm for such a beautiful gadget 🤓 I'll be installing my Nest Thermostat 3rd tomorrow, can't wait 🥳

[@Bootstrappin]

Def still one of my favorites, never gets old to do something so mundane as changing the temperature! Enjoy!

[@joshuaphurkotum9292]

Still needs a c wire. 😅😅😅

[@Retro.Studio]

Did you use the heathlink? Or just a simply replacement for the old Honeywell?

[@Bootstrappin]

Only a replacement for the Honeywell, I don't know what the Heatlink is.

[@Retro.Studio]

@@Bootstrappin i forgot..you’re living in the USA right? Here in Europe a Nest thermostat will only work with a Nest Heath Link

[@Bootstrappin]

@@Retro.Studio ohh gotcha.

[@zoraxc4]

That for only heat ! Thank hope it work

[@amandashanks688]

I hooked mine up just like you said and had the same exact previous thermostat as you but now it just keeps turning our heat on even though the house is way hotter than I indicated we would want heat on. It is 88 in here and I said to turn heat in at 60. Any suggestions?

[@Bootstrappin]

That's strange. So the Nest is working I assume, but it kicks the heat on. Do you have AC?

[@scottgrimard198]

I have the same issue the furnace will not stop heating I have it set to off but still consistently running

[@ttate9954]

@@scottgrimard198 Hello Scott we are encountering the same issue. Called Nest and they gave us "possibilities". No concrete reason. Did you find a solution if you don't mind sharing.

[@scottgrimard198]

@@ttate9954 yes we did, it was a defect with the thermostat, got a new one installed it and worked!

[@scottgrimard198]

Keep me posted I know that thing inside and out now Haha.

[@davidtibbitts4009]

I have the same two wire and simulator thermostat. The only thing I was it was say it was not hooked up to r1 or r2. I think this may have helped

[@dede6110]

anyone has the short cycling problem? i installed the 3rd gen nest with same only two wires. it works the first year, right now the thermostat will show up low battery and the heat will turn on for 2 and half min and shut off itslef and keep repeating.

[@sk8in4sam]

Thanks for the help and the entertainment.

[@Bootstrappin]

You're welcome!

[@anamericanentrepreneur]

I agree about that cool nest screw driver 🤣

[@Bootstrappin]

Thank you, I thought I was taking CRAZY PILLS

[@mikecynkar5384]

Question, I have a yellow wire coming out of my forced air furnace that is spliced into a red wire, then a white coming from the furnace. two wire system, on the schematic it shows this yellow wire with the writing field "installed thermostat and low voltage wiring" along with 24v sec written along the yellow wire path. So can this yellow be jumper off of to make a C wire for another wifi thermostat, or better just to go the two wire path you did here?

[@Bootstrappin]

Sounds like it could be, though the yellow seems like it's a 24VAC supply wire, not C.

[@mikecynkar5384]

@@Bootstrappin isnt that all the c wire is though? Sorry if that is a stupid question.

[@mikecynkar5384]

I think I figured it out, it needs to be a continuous 24v. Make sense, ill bust out the multimeter. or just buy a nest.

[@Bootstrappin]

@@mikecynkar5384 not at all. The C wire is usually referred to as the 'common' wire, or 0V. The yellow usually is for the 'cool' air conditioning wire, from what I'm reading.

[@juanaimbach7179]

Thanks

[@Blackdog4818]

So this will start my heat and AC?

[@Bootstrappin]

Not with two wires. This is heat only. AC usually has more wires.

[@Blackdog4818]

@@Bootstrappin Ordered a NEST since it was on sale for $199. As Arnold says, "I'll be back." LOL.

[@Bootstrappin]

@@Blackdog4818 oh shit lol. Good luck, shouldn't be too bad though. I have another video on installing Nest with HVAC

[@Blackdog4818]

@@Bootstrappin So good news is I have 4 wires in the back of my thermostat, White to "W", Yellow to "Y", and Green to "G". My red wire though is jumped between HR and HC which would be quite a stretch on the NEST. Do I need to repeat this jump with the NEST? Or can I just stick it in HR?

[@Bootstrappin]

@@Blackdog4818 you could always just see what happens, but I'd keep the jumper. Could be an HVAC specific reason, so I like to keep what I find. Nest generally does a good job telling you if something is wired funny.

[@chrismichaels4966]

I tried this and the thermostat kept going higher and higher. I had to shut it off. I have radiators with a boiler, and my electrician said I needed a common wire with this system. So, then the boiler I have doesn’t use a common wire (?) so he had to run a relay. Long story short - this may not necessarily work as instructed in the video, depending on what kind of heating system you have.

[@Bootstrappin]

This is true. All boilers seem different, I'm starting to hear rumblings about Google updating the Nests to no longer support the two wire option. Hopefully not as an 'over the air' update, and suddenly tons of Nests will stop working.

[@sean1483]

Installed on two wire systems furnace cycles runs for a sec and shuts down ???? What do I do

[@Bootstrappin]

Does the Nest lose power/show any errors or anything like that?

[@deepthistar87]

Do you have ac with ur HVAC...does it turn on

[@Bootstrappin]

I do not, this is a heat-only system

[@deepthistar87]

@@Bootstrappin thanks

[@NewsBroadcasting]

is it possible ot access it via built in webserver via computer?

[@Bootstrappin]

You can access it through phone and computer using an app or webpage

[@ES-fr3yz]

So,what's charging the battery if you only have two wires?

[@Stoner916sac]

Dude its A/C voltage. Those two wires carry power when the heat cycles off, charging the battery. When they are shorted, they do not charge the unit, but it has enough time over a day to fully charge

[@MrAshwindersingh]

thsank you i am going to instal today

[@hongc2263]

just installed，why my fan keep running？

[@Bootstrappin]

If you have a fan, you can't have two wires, so something was probably wired wrong. I believe fan is supposed to go to 'G'. Nest also has the ability to keep the fan turned on, so check settings as well.

[@cowboybuddhaful]

Shouldn't the white wire go for W??

[@ttucci29]

Did you used the e link ?

[@devonledford4036]

I did this however mine keeps requiring a heat pump wire in o/b

[@gerardosalas9477]

Are you the guy from regular car reviews? Lol

[@Bootstrappin]

I'm Mr. Regular's less popular weird brother

[@modelmale615]

mine did not work with 2 wire, I had to adapt a 24 volt adapter

[@stealhty1]

Thx for share ,I really really dont want to go the long path of having to installing a C Wire power supply

[@EscobarMT]

I have a stupid question! What's the black wire? I have 3 wires 🔴,🌕 and ⚫ will this be compatible with nest gen 3? And where would the black wire go? Help please! Thanks,

[@Bootstrappin]

Unfortunately there's no real standard when it comes to thermostats. You need to note where those wires go on your old thermostat and just copy that over to the Nest. Could just be a common wire, which would go to 'C'.

[@hewhoknows9135]

Your video is awesome....that is all

[@Bootstrappin]

Thank you!

[@MrAshwindersingh]

do we need c wire ?

[@Bootstrappin]

Sometimes -- it depends if your boiler can supply enough current. If not, you may need a C-wire maker or adapter -- I have a link in the description to both.

[@ljm_gaming4913]

My new Honeywell thermostat only has 2 wires, but they are labelled a and b, and both wired are grey.

[@legolwa]

is your's a WIFI thermostat or a regular one? For an older 2-wire, I don't think it matters. Connect either wire where you want.

[@ZteveW]

Won’t you need a common wire to keep that internal battery charged?

[@Bootstrappin]

I didn't need one. It depends -- some furnaces can supply enough current through just these two wires to power the Nest/charge the battery. If not though then yes -- you'll need to install either the Nest C connector, amzn.to/3tcWwzq or run an adapter's C wire amzn.to/3qvVTOu.

[@lesio333]

Why they say that you need a C wire? Did it worked because there was a call for heat? Would it work with a forced air heat and AC?

[@Bootstrappin]

Because in certain cases the Nest is incompatible unless you have that C wire. Only one way to find out I suppose. I don't see why not, but you'd have extra control wires for the fan(s) and air conditioner.

[@hrvpictures7786]

What if The wires are 120v, can you please help?

[@Bootstrappin]

Don't know anything about that, sorry. Google "convert 120V to 24V thermostat".

[@angelorosajr.598]

My thermostat is a Honeywell heat only. It has 2 wires. A red and a green. No white. The red goes to R and the green goes to G?

[@BiteTheCurbNow]

No. R AND W - it doesn't matter if it's 2 wire... Or what TWO colors. Connect to R and W.

[@loveislife77]

@4:40 -- thanks for this disclaimer. you saved my ass