Thank you! Our HVAC guy wanted $500 to do this job. After watching this video I spent $40 and 30 minutes of my time and it is done. Also, in case someone else encounters this, mine had a white and red wire. Turns out the red one in my case was the same as the black in this video.

Thank you John!! Could not have done this without your video. Used the same model and installation only took a few minutes. I now have heat again! The old analog one died last night and I've been freezing all night, but thanks to you it is all good now.

The manual doesn't go over 2 wire, so come to youtube. Thank you John! I'll be back to watch more of your videos. To the point and helpful.

Thanks John. The manual might as well have been written in hieroglyphics, they made no attempt to help the 2 wire guy whatsoever. You DA man!!! Subbed and liked.

Thank you so much for this video. My thermostat went bad last night and it was freezing. Went to Lowes this morning hooked up everything and it took off! I'm one happy and warm lady! 🙏

Thank you John! That was super helpful in replacing our old two wire thermostat! First time doing any home electrical work and it worked! Yay!

You helped me replace one of my thermostats two years ago. I came back to your video today for help replacing the other one. Thank you so much.

I watched this video before installing mine on a ~40 year old furnace with Honeywell control unit, and Honeywell Mercury thermostat. When I removed the ancient 2-wire Thermostat, the Terminals were labeled W and R. So verifying they kept the same nomenclature, even if they don't give instructions for old 2-wire systems. This further backs the instructions here. Works great now.

Thank you!!!!! I can’t believe Honeywell didn’t show how to hook up a system with only two wires. Your video helped.

Thanks John! Helped me out a lot. Got my mum setup with the new digital meter and she’s happy now. Great video thank you for sharing it

This was perfect. I was having trouble doing the identical upgrade and it turns out the original installer had the white and black reversed. There was also a Y stamp next to the black to further confuse me. Seeing where your wires were was exactly what I needed. The instructions provided with the RTH2300B are quite vague. Great descriptive video. Much appreciated

Thank you so much for making this video, I have the exact same old mercury thermostat and purchased almost the identical new Honeywell controller, and the 5-wire instructions had me flummoxed thinking I'd have to return it. Nope! This video was just what I needed to hook everything up properly!

Thank you, thank you, thank you. Even though we installed a different Honeywell model, this was exactly what we needed to connect the two wires (the instruction manual was not helpful).

Thank goodness for people that take the time to do these videos. Just to add if you have a red and green wire like me, put the green wire in the w slot. Thank You again John for posting.

John you are the man I will never get this done without your help you save me a lot!!!!

Nice job! I got 2 of these from a Home Energy Survey, Opened it up, and thought, oh well, my system is just too old for this. Then I found this video. Now I'm up and running. You've done a great job here, very thorough. Honeywell should be paying you for this. Wonder how many have thrown these thermostats into the trash or returned them because there were NO Instructions. Great work.

Hey John... nice, simple, clear video. These are the kinds of things that make KZfaq so valuable for so many of us. Thank you for taking the time to post this. Since repairs are so expensive, I often simply experiment with things I don’t know. Since I don’t know how to figure out which wire is constant hot, will I ruin the thermostat by having the two wires transposed, or will it simply not work?

Many thanks! Saved me a bunch of stress. Watched your video a few times, bought a similar unit and installed it in 2 minutes!

Thank you! After watching your detail instructions, I have more confidence in installing the thermostat by myself.

I was about to return my new thermostat until I saw this video. Thank you for posting this, you're a lifesaver

Thanks for the video. My old thermostat didn't want to work anymore. Installed new one and it worked. Very easy steps. Thank you.

Thanks for this video. I hate calling companies to get help. On the phone for hrs. This really helped me out

John that was super helpful. I could not get this T-stat functioning without your video.. Cheers,

You are freaking awesome!! I looked everywhere and nobody has this!! Well done sir

Thanks man, just what I needed with my non programmable Honeywell thermostat. They really need to update their documentation.

I just happened to have the identical digital thermostat, thank you so much for posting this!

Thank you. I was confused when I only saw 4 wire instructions. I also have a white and black wire in the garage, this was exactly what I needed.

Thanks so much, John! The instructions booklet was useless, and you saved me hours!

Thank you so much, John. I just wired mine successfully after handyman couldn't figure it out. Very helpful video!

THANK YOU for making this video! i was completely unsure of what kind of replacement to get or how to install it since it only had the 2 wires. and the hardware store here doesnt carry the old style. we were cold, and now we are not. THANK YOU! while i do not recommend it, it was 20 degrees Fahrenheit outside and 55 inside, i jumped the 2 wires with the handle from a binder clip with a rubberband around the middle for me to hold. this essentially did what the thermostat would do and closed the connection, telling the furnace to turn on. i did not leave it unattended. and it got the house back up to 70 until i could get the new one installed. it was only like that for a couple of hours. but it did the job. as i said... i DO NOT recommend anyone do this. it could start a fire if the resistance of the wire used creates too much heat. after i got the new wall plate installed i realized i didnt have a teensy tiny itty bitty screwdriver to connect the wires. at that point i remembered i had my multimeter test leads and so used that to jump them until i could acquire the proper tool. besides the tool issue, and the screws they included not being very good (i had trouble getting them into the drywall, should have drilled pilot holes to begin with), thanks to this video, it was a piece of cake.

Thanks John. Found it useful. We are replacing the old manual Honeywell Round thermostat with a Honeywell RTH221B1021/E1 RTH221B1021/A 1 Week Programmable Thermostat. With the old thermostat cover off I only see a white and a pink (faded red?) wire screwed to the base plate contacts so I have to assume it is a 2-wire system (Oil fired, Hot Air, Heat Only). My wife is tired after several heating seasons of changing the temperature settings 2-4 times daily manually, She went to bed early one night and forgot to turn down the heat. We got so warm we ended up getting up at 2AM to turn it back down, It would be great just to set it once and let it run!

Thanks, this was just what I needed, Honeywell should pay ya for this instructional video! Lol. Cheers

NICELY done - clear concise instructions using words the average home 'Fixer' understands.... thanks for that - instantly understood where I went wrong hooking it back up. TIGHT!

Thank you--very helpful. My system has a red and a yellow wire. New thermostat working great.

Thanks for help. So simple, but yet so confusing. My old one in old home I bought was wired backwards with phone line, but somehow worked for last 30 years. I went to hardware store and got proper color coded wire. Forget getting any help from Honeywell, I was on their assist line waiting for 1.5 hours till they finally disconnected me. It is amazing Honeywell can stay in business when they cannot write simple easy instructions or be able to have a functional consumer help line. I guess they want you to hire their repair guys to charge the sky for a 15 minute install.

The very useful video that helped me replace our 2 wire White Rodgers thermostat with honeywell home non-programmable thermostat. Thank you for this.

Thank you so much bro, real simple the way you explained it , was going crazy with the other videos ! God bless you brother !

Thank you ! You explained everythings so well and I was able to replace the old mercury thermostat myself 😀👍🏻

your awesome. thought i lost 300 bucks when i bought mine till you explained 2 wire set up great videos keep it up

Thank you! I have an older home with only a black and white! You saved me!

Thank you sooo much! You did such a great job explaining this. Way better than the “instructions”. Awesome!!

Thank you so much for this video John! You saved me hours of my time (and potentially my marriage! 😂)

thanks man that helped a lot,i'm using it on a oil furnace in the shop,i'm bad to leave it on at night time maybe you and the thermostat will fix 2 problems

How do you hook up the blower fan so it runs separately without the heat on?

Great video. I'm replacing a very old Iron Fireman thermostat with a Honeywell unit similar to the one in the video. My Honeywell unit is non-programmable but that shouldn't make a difference. My problem is that the two wires on the Iron Fireman unit are labelled Common and Day. I don't know how to interpret those wires and where each should go on the Honeywell unit. I've searched and searched but found no reference to the Iron Fireman wire nomenclature. Thanks.

Thank you so much for this video. Honeywell does a lousy job in their instructions as you stated by not showing a simple two wire install. You explained it well and did a wonderful job thank you again may God bless you

Thanx a lot. Just installed one today with the exact same new one.

Thank you so much John. Saved me a bunch of time. My mom is happy too!😁

John P, I have the same thermostat as you and hooked it up the way you said. The furnace works but the fan only switch doesn't. Any idea how I can get just the fan to work by itself?

Question about this style. I am trying to replace all 11 baseboard heating thermostat. Behind the first one I took apart I have to White Twisted together and I have two black wires connected to the thermostat. First question is this still considered a single pole or a double pole. Second question do I just use the two black wires? Because if so I have the power turned off at the fuse box because that heater would never turn off even during the summer when we bought this house

Thank you! You just saved me a ton.

Thanks. No one else showed what to do with only two wires.

Hey John, followed your two wire instruction! Any idea how to deal with an inverse thermostat? When I turn the heat up, my heater turns off not delivering heat. But once I turn the heat down, my heat turns on. The wire colors are white and black just like your video

Awesome! What took me a few hours to try to complete before I found your video took me a few minutes to complete after watching your video. Thank you! :)

Thanks , I just installed the same thermostat with 2 wires.

Excellent, thanks for the information - was needed as like you said 2 wire is not in the manual.

great video. Just what I was looking for.

Perfect for what I needed! Thanks!

Great video and very informative. Thank you!

Great video! Our system has water heated with gas but the igniter uses electricity; where do I put the switch and does it matter whether the switch is set to gas or electric?

I had given up on my thermostat until watching this. Thank you thank you?

Thank you! This helped perfectly!

Thanks! I needed this exact info!

Thanks for the great video, going to try to install it today for our oil furnace

Thanks for the great video. Any idea if this product would work for a gas fireplace ? Thanks

Thank you so much! Great explanation! I was able to follow and install thermostat myself!🎉

if you buy a smart thermostat with wifi is it the same. I only have heat in my cabin. would be nice to control from a distance. thanks for the video.

Nice clear video. When using two wires, can it be programmed for different times? Thank you

John thanks great job, why couldn't Honeywell have made it this simple!

Very helpful ! Thank you so much.

Thanks! 100% what I needed info on.

Thank you for this video!!! Exactly what i needed.

how do you connect on the other end when the oil furnance produces hot water also?

Great video super helpful. Well done. Thank you!

Very informative, thank you for the instructions!

Very helpful! Thanks for sharing.

I have a gas heat only system with a red wire connected to RH and a whitish wire connected to W with another light red wire jump connected to RH and RC. I am wondering if this jump connector wire can be ignored in the new thermostat?

OMG... John!!!! Thank you so very much. You are awesome!!

good looking out brother keep up the good work

John is this system millivolts? I have a very very old boiler and am looking for something that works with millivolts from a thermocoupler, as that is how my system works

Thanks. Wonder why Honeywell did not include instructions for people like us who still have the 2wire thermostat. Called their 1800 number but it’s taking forever to get connected to an available install support. Faster to Google and found this video.

If I have heat & cold AC unit with the 2 wires do I leave the bridge pin on the R & RC?

Helpful video! Thank you!

Thank you, simply and easy instructions

Although I'm buying a non programming one different model sorta like the one I have except 40 or so years newer this helps alot. The heater is so old that parts are nearly impossible to find. My uncle had to add wiring to the existing wires as they broke which works although a pain to refix for me but I'm sure it's the thermostat now thats not causing it to kick on. It clicks then nothing but at least the pilot light and blower is still good. The thing is so loose on the wall from usage even if that's not the issue it's one new part and I cant afford 5000 or more to replace the entire unit . Thanks for this video I will try it as soon as I get the part. I'm freezing and my electric heater melted to my extension cord the other day. 😫

Since this is an older video I'm not sure if you will see this...or perhaps another view may respond. Our thermostat is a heat only, forced air system. It doesn't have a switch to turn the fan on. Since we don't have central air it would be a pain in the butt to install AC units in our windows as they are the large side-slide windows, not a double hung. My thought is I would like to turn on the blower fan in the furnace to draw in the cool air in the basement and circulate that cooler air up to the main level in an attempt to cool it off a bit during summer. You mentioned at 6:35 you don't have a fan wire hooked up so that switch is not used. Does that mean I would have to rewire just to turn the fan on?

Do you have to remove the bridge between r and rc if you don’t have ac

It is useful!!! Thank you!

I have the exact same one but how do I hook it up with multi wiring blue yellow white green and red

Waterheat control does it work the same

I have a yellow and white wire. How will this work?

After removing the old Mercury thermostat, how do you recommend I dispose of it?

This video was helpful. I just purchased a similar thermostat. I did not take the bridge out of the R & RC terminals. Will this impact the function? I connected my red wire to the R.

Just what i needed. I have an old system

Does the bridge have to be removed or can I keep it in there?

I had the same old thermostat as you. Red was constant black was variable 😂

Hi John. I followed the instructions, checked the wires several times, but our furnace won't start. I set the temperature extra high to drigger it, just to make sure it works. Nothing.

Hello on my old Honeywell round thermostat heat only, my wires are Blue wire and White wire. My bro placed the new Saswell programmable thermostat wires at RH and W and since last night we have no heat. Please advise.

Hope fully yours will work as described , if not good luck with their off shore help desk .as they read the same manual that came with it , I was told by their so-called help desk buy another one .

John, Can that be programmed to turn on and off at different temperatures? i.e. on @65 off @ 70 degrees or some kind of "dead zone" adjustment?