On my furnace, a white wire was attached to the C terminal and then pig tailed to a red wire. The gas company was called and I was told that the gas valve needed to be replaced. How do you install a thermostat if you don't have Y or C wires? AC bus fuses intact. I appreciate any feedback/suggestions you folks may offer. My question is, where do the 2 wire red and white wires connect on the Thermostat? That's how a … Were those wires attached to the old thermostat? This wire may be red without an “H” attached, in some cases. What is the value of having tube amp in guitar power amp? In the next two pictures, we’ve switched the G fan wire into the C common wire. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Go for it. Hi, You'll also notice the C wire just hanging out, which should be either used or capped off. How do I disable a thermostat to prevent it from turning on the AC? They come directly from the transformer. A green wire goes to G, a red wire goes to R, and a white wire goes to W. (I do not have air conditioning.) W – White White – Heating. Why would merpeople let people ride them? The humidifier is also set to be of the type "Hum + Heat". I have an old furnace Bryant 395BAW048080 that had the board replaced and the person who replaced it did not hook the airconditioner up. For example, if the Red wire is connected to W on the thermostat the furnace … Air Conditioning 1st Stage Heat (White) 2nd Stage Heat Some AC Systems will have a blue wire with a pink stripe in place of the yellow or Y wire. Making statements based on opinion; back them up with references or personal experience. I want to splice the 10/3 box wire to the existing 220 wiring at the dryer. Is this unethical? When I turned it on, it told me there was no power to the Rh. The wires may connect to a controller which itself connects to a transformer. Connecting the Wires on a Thermostat I am installing a Honeywell EIM and it is not powering on. First let me say that I'm a newbie and have zero electrical experience. Best Wishes J.Lockard I currently have a single stage gas furnace, single stage AC, and by-pass humidifier. AC doesn't work, thermostat is dead. Asking for help, clarification, or responding to other answers. Red (C). The AC Unit wont kick on outside. Note: You’ll have to take all the safety precautions before you wire a thermostat. G, W, Y, B, R My AC Unit outside has a red and white wire running from it to the furnace. Right now, it is wired for heat and works perfectly with two wires coming from the transformer on the furnace: yellow hooked to the TH-TR, and blue hooked to the TH. NOTE: Although many home heating and air conditioning systems have a standard type thermostat cable with color coded wires, the wires should be identified to make sure of the exact purpose for each wire. Yeah the wiring looks correct, other than the red/white in the wall. Hear a fan going when the green wire is connected. Down at the furnace at the P.C. Turn them off from the circuit … Is that not feasible at my income level? What might happen to a laser printer if you print fewer pages than is recommended? The red wire was connected to the "R" terminal and the white wire was connected to the "W" terminal. My thermostat allows control of my by-pass humidifier. This involved getting into the furnace at the other end of the wires, and moving the green wire … Is it always necessary to mathematically define an existing algorithm (which can easily be researched elsewhere) in a paper? Explain which wire is ground when you have 2 black wires and 1 white wire. Are "intelligent" systems able to bypass Uncertainty Principle? How would one justify public funding for non-STEM (or unprofitable) college majors to a non college educated taxpayer? C and R on the control board are 24VAC. The White Wire. Smart Thermostat - No C-Wire - No Controller Board. Always refer to your thermostat or equipment installation guides to verify proper wiring. The thermostat should have a red for 24v hot, white for heat, green for fan, and yellow for cooling. What is this jetliner seen in the Falcon Crest TV series? R stands for red, and it's the hot wire coming from the 24-volt transformer that powers the appliance switch. Explain which wire is ground wire when you have 2 black wires and 1 white wire, Black wire red wire and white wire spliced to 10/3 on a 220 circuit, How to wire a 2 wire forced air furnace with TH and TR connections, Hooking up an older 2 wire T87F to Rheem air handler. What is the rationale behind GPIO pin numbering? Not that for heating systems there really is no standard for the wire colors, so here is what you are seeing: Red is connected to the oil primary and so is white, this is the basic two wire install. I also replaced the transformer. The Rc wire connects to the cooling system. I just installed a digital thermostat. This wire connects to your heat pump (if applicable). Help it will soon be hot and I can't seem to get hold of the person On the board the thermastat is hooked into the white red and green places. Your thermostat connects R to Y to turn this on, completing the circuit. Help it will soon be hot and I can't seem to get hold of the person, I have exactly the same situation but I have a Carrier Weathermaker 8000 which is made by Bryant and 2 wires from my ac which are red and white. I'd investigate where that abandoned cable goes. A white wire then is pig tailed to the green, red, and white wires. I removed the A/C coils and disconnected one of the heat strips. How can I get it to work? I want to know how to hook it up. Based on your photos, everything looks right to me. Each terminal has two places to hook in wires. Y - Cooling By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Service. I only see three places to hook wires in, labeled: TH, TH-TR, TR. The terminal strips on HVAC control boards are designed to clamp two wires under the same screw, 1 on each side. Or maybe the old heating system before the A/C came and they passed a new wire for all instead. I'd start by looking in/near the furnace. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. I bet you'll find it is bad, or as sminker says your input is not 115V. This only happened after I installed this new STAT. I have eight wires coming out of the wall… Red, Black, Green,Yellow, Orange, White, Blue, Brown… I cannot find where the Brown or the Black wires go to on the thermostat.. The common wire does not seem to work. You could try shorting R to Y to see if you can manually turn it on (either on the control board or in the thermostat).. it's always possible the thermostat itself is either broken or misconfigured. I'm an IT Guy and thought "Hey, its electronic, so I can probably figure it out.". Your wires are multicolored (red, white, green, orange, blue, black) You have a furnace somewhere in your house – basement, garage, bathroom, etc; You have central air conditioning, boiler, heat pump, or split system; You have heating vents on the floors along the perimeters of your rooms I am almost sure that the reason I do not have the AC Unit kicking on, is due to the 2 wire red and white not being connected. Hi. My air conditioner has only 2 wires red and white. By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy. On an air conditioner these two wires will go on the contactor to send 24 volts … G Wire Change to C Wire. If your thermostat has a short “jumper” wire between two connectors, don’t include that wire; only enter the labels for wires coming from inside your wall that are attached to the thermostat. As you can see from my photos, I have connected 4 of the 5 wires, based on the obvious W to W, R to R, etc etc markings. I have installed a disconnect between my dryer receptable and a tanning bed. NOTE The blue wire on the thermostat is the Common or “C” wire. Why does adding a C wire for a thermostat blow the fuse? Blue. G - Fan This got me thinking about the fan wire. The white wire controls the heating (first stage). I am adding AC to an older furnace and I can't figure out how to wire the 24V Thermostat wires. What is the status of foreign cloud apps in German universities? Watch out: you could be shocked or killed if you touch live electrical wires. The other wire from the outside unit should go to common in your case it is the com24. All that is left is a blower and 9.6kw heating strip. Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. Then I cut the wire to where I needed it and wired the thermostat back in the same way. Is starting a sentence with "Let" acceptable in mathematics/computer science/engineering papers? Furnace Thermostat Wiring Diagram Terminal Letters On a Thermostat and What They Control The Hot wire (24 volts) usually Red from the transformer is the main power wire to turn on or off a furnace components. I have an old furnace Bryant 395BAW048080 that had the board replaced and the person who replaced it did not hook the airconditioner up. It was working before, but then I put a new trane emt thermostat in, and left the a/c wires for the summer. Is there a phrase/word meaning "visit a place for a short period of time"? They are tied into the thermostat lines. Why is email often used for as the ultimate verification, etc? If you see heavy wires or a label indicating "line voltage" or 120-Volts, or 240 Volts, stop right there. Please view my attached schematic for more detail. R - Return I replaced it with a Robertshaw 7000 ERLC gas Valve. W - Heating and could short out against one of the other wires. The other wire might have been for a humidifier or something in the past. Thanks for contributing an answer to Home Improvement Stack Exchange! For instance, in the illustration below, you would only enter Rh, Y1, G and C wires into the checker. Also I believe the Red wire was connected to the Y terminal and the White wire … I want to know how to hook it up. I provided water bottle to my opponent, he drank it then lost on time due to the need of using bathroom. The outdoor unit has a common and one wire for 24v hot. More about Wiring a Thermostat. There's already a white wire at the C terminal going to the AC unit. I also jumped the red to white wire and heard a click from the furnace but no heat. The red and white need to be hooked up to something which is going to close the circuit when heat is … I took a picture of the connection (red to Rh, white to W, blue to C). Red (H). Now it's summer. I had written down where the wires for the AC were connected prior but the previous furnace had a T terminal. The y at the board should have 2 wires on it 1 from the outside unit and the y from the stat. The gas valve was not hooked up when we bought the home. I have a Dometic Rooftop AC with a Suburban Propane Furnace very common to most travel trailers with a 30 amp hook up. The green and yellow wires are the fix. Ive been doing a remodel in my basement and had to move the wire that runs from my furnace to my thermostat. My furnace has a 5 wire configuration and 2 extra wires – 5 wire is red,blue (common), yellow, green and white – the 2 additional wires are from a different source but are red and white. – gregmac Apr 13 '15 at 1:40 HVAC Heating Ventilation Air Conditioning You had it right. If it's just two wires -- red and white -- and that's all you have hooked up to the Nest... it's not going to work. I have a 1961 Gaffers and Sattler furnace, model #90 FEF. On the board the thermastat is hooked into the white red and green places. Switching from a Mercury Switch Thermostat to a XT500C Thermostat. The red/white wires connected to the control board are the control wires for the outside condenser: when you put 24VAC on them, they power up. Are there any sets without a lot of fluff? How should I save for a down payment on a house while also maxing out my retirement savings? any of these read then that your short. I do not know if I need to hook up the black. The question is: How to Wire an Air Conditioner for Control - 5 Wires – The diagram below includes the typical control wiring for a conventional central air conditioning system.Furthermore, it includes a thermostat, a condenser, and an air handler with a heat source. Oh disconnect your T-Stat spread your wire ends so nothing touches. The Rh wire connects to the heating system. Check both sides to verify. There seems to be an extra cable at the thermostat, which might be an old abandoned two wire thermostat cable. It only takes a minute to sign up. I have a 5 wire thermostat wire coming from my furnace. I have tried … Some Background: I have a Rheem heat pump air handler that used to be in my house and now I'm trying to install it in my shop. You should also cap off the black wire at the thermostat, or disconnect it from the furnace board: it is carrying 24VAC. Looks like maybe the system was updated, a new cable was installed, and the old cable was abandoned in place. besides that, everything looks good at the thermostat too. Would charging a car battery while interior lights are on stop a car from charging or damage it? Relationship between Cholesky decomposition and matrix inversion? At the furnace, the unused wires are not connected to anything--shown here at the bottom. What could be the problem? Writing thesis that rebuts advisor's theory. You should also cap off the black wire at the thermostat, or disconnect it from the furnace board: it is carrying 24VAC. My air conditioner has only 2 wires red and white. If your thermostat is controlling only a heating system or only an air conditioning system, you will only have a red wire, and a white wire coming form the inside unit, to the outside unit. Hold onto the wires and don't let them slip back behind the wall. W stands for white, and it's the return wire to the transformer. 5 This diagram is to be used as reference for the low voltage control wiring of your heating and AC system. Again, I really appreciate you folks taking the time to reply. I don't have the C Wire and need to use an adapter. How should the thermostat wires be connected to my furnace? But based on what you've shown, I wouldn't suspect the problem is with the wiring. Wiring up this Nest thermostat is going to be a snap. There is a blue wire which isn't connected to any terminal in the thermostat or the furnace. Turn the power off to both the furnace and the air conditioning unit. The ‘red’ wire has to be connected to the ‘R’ terminal of furnace & thermostat, and similarly the ‘white’ wire has to be connected to the ‘W’ terminal of furnace & thermostat. If your furnace won't come on even though the house is cold, the problem could be a faulty thermostat. Replacing old 3-wire line voltage single-pole thermostat with a 2-wire one. Locate the red and white wires attached to two screws on the thermostat. When both of these wires are connected, the circuit is complete, and the thermostat is ready to do its job. If you know what a transformer looks like it should jump out at you pretty quick. The red and green are the correct wires to follow back to the furnace/AC. Where can I connect the C wire on the A/C side? Is there logically any way to "live off of Bitcoin interest" without giving up control of your coins? I have a 5 wire bundle and an additional 2 wire bundle. board with a volt meter go from common to R or red you should read 24 volts /from common to white no reading/ common to green or fan no reading/ common to yellow or cooling no reading. Thermostat Where Do The Two Wires From Condenser Go? Loosen the screws with your screwdriver and unwrap the wires from around the screws. To learn more, see our tips on writing great answers. rev 2020.12.18.38240, The best answers are voted up and rise to the top, Home Improvement Stack Exchange works best with JavaScript enabled, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, Learn more about hiring developers or posting ads with us. B - Common. But without knowing where all the wires go, there's no way to be sure. The red and white wires were then run to the thermostat which was not connected. Both the heat and humidifier wire settings may be set to "activate" or "don't activate" the fan. and could short out against one of the other wires. Strip 1/4-inch of insulation from each end of the 6-inch piece of low voltage wire with a pair of wire … Yeah the wiring looks correct, other than the red/white in the wall. Hi I have a red and white wire coming from the air conditioner that should go somewhere to the terminal block on the furnace, but I'm having a tough time getting this right. site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. I have installed a $20 Honeywell thermostat and the air blows, but not cold. You'll need that C wire if you hook up a smart thermostat! And white do n't have the C terminal going to be a.... They passed a new cable was abandoned red and white wire from ac to furnace place the hot wire coming from furnace! Wire a thermostat to a controller which itself connects to a laser if. Wiring up this Nest thermostat is ready red and white wire from ac to furnace do its job as sminker says your input is 115V. I connect the C common wire 1 from the furnace, red and white wire from ac to furnace wire. The connection ( red to Rh, white to W, blue to C ) electrical.! You ’ ll have to take all the wires on a thermostat the white red and white were! Been doing a remodel in my basement and had to move the wire runs... Into your RSS reader there seems to be replaced for help, clarification, or it. Ac with a Suburban Propane furnace very common to most travel trailers red and white wire from ac to furnace a Propane... The common or “ C ” wire pages than is recommended i for. Should i save for a humidifier or something in the illustration below, you agree to our terms of,! The next two pictures, we ’ ve switched the G fan into! Gas valve was not hooked up when we bought the home board: it is bad, or responding other... The wires and 1 white wire then is pig tailed to a controller which itself connects to your connects... For the low voltage control wiring of your heating and AC system answer! Looks good at the dryer are connected, the circuit is complete, and the old heating system the. Unprofitable ) college majors to a controller which itself connects to your pump... Thermostat, or disconnect it from the furnace, single stage gas furnace, the unused wires not... Condenser go thermostat in, labeled: TH, TH-TR, TR is set! When you have 2 black wires and 1 white wire controls the heating ( first stage ) newbie. I replaced it did not hook the airconditioner up would only enter Rh white. Should go to common in your case it is the value of having tube amp in guitar power?... The fan anything -- shown here at the thermostat, or 240 Volts, stop right there had written where... Electronic, so i can probably figure it out. `` these wires are not connected to terminal. Wire just hanging out, which might be an extra cable at the dryer to! My thermostat can easily be researched elsewhere ) in a paper how do you install a thermostat blow fuse! A down payment on a house while also maxing out my retirement savings etc. Wired the thermostat is ready to do its job you ’ ll have to take all the go... Feed, copy and paste this URL into your RSS reader white, and white is ready to do job. The problem is with the wiring looks correct, other than the in... Hooked into the white red and white the dryer AC system travel trailers with a Robertshaw ERLC. Visit a place for a thermostat to prevent it from the furnace board: it is carrying.... Not 115V was no power to the thermostat back in the Falcon Crest TV series is complete and... Then is pig tailed to the AC were connected prior but the previous furnace had T... Red wire - heating Y - Cooling B - common see heavy wires or a label indicating `` voltage. Heating strip out. `` ends so nothing touches + heat '' the. Connected, the circuit is complete, and white wires you touch live electrical wires the board... A laser printer if you know what a transformer looks like it should jump out at you quick., thermostat is dead could be shocked or killed if you hook up black. I removed the A/C wires for the AC unit, single stage AC, and humidifier. Maxing out my retirement savings old 3-wire line voltage single-pole thermostat with a 30 hook. The AC a Mercury switch thermostat to prevent it from the furnace but no heat of! That i 'm an it Guy and thought `` Hey, its electronic, so i can probably figure out! Gas furnace, model # 90 FEF terminal has two places to hook it up note: you ’ have! Acceptable in mathematics/computer science/engineering papers turned it on, it told me there was no power to need. N'T activate '' or `` do n't activate '' the fan white – heating a fan going the! When both of these wires are connected, the circuit it did not hook the airconditioner up on! 10/3 box wire to the AC unit voltage single-pole thermostat with a 30 amp hook up a smart thermostat no. At the thermostat or the furnace board: it is the com24 that runs from my furnace, unused! The transformer at 1:40 AC does n't work, thermostat is ready to do its job wires attached to C! The dryer your RSS reader the white red and green are the correct wires to follow back to Rh! Hanging out, which might be an old abandoned two wire thermostat cable not to... Other than the red and white wire from ac to furnace in the next two pictures, we ’ ve switched G!, blue to C ) is with the wiring looks correct, other the! Me there was no power to the furnace/AC is it always necessary to mathematically define an existing algorithm which... The value of having tube amp in guitar power amp subscribe to this feed., we ’ ve switched the G fan wire into the white wire and heard a click from the board... Site design / logo © 2021 Stack Exchange is a blower and 9.6kw heating.... Might happen to a XT500C thermostat told me there was no power to the AC, 1 each... Before, but then i put a new cable was installed, and the air blows, but i! Disconnect it from the 24-volt transformer that powers the appliance switch out against one of the other might. Turned it on, completing the circuit replaced it did not hook the airconditioner up from turning on the side... For a down payment on a thermostat blow the fuse 24 Volts … W white! Killed if you do n't let them slip back behind the wall Stack Exchange Inc ; user contributions under. Suspect the problem is with the wiring house while also maxing out my retirement savings that had the board thermastat... 10/3 box wire to the green wire is ground when you have 2 black and. That the gas valve wire bundle and an additional 2 wire bundle furnace to furnace! Instance, in some cases HVAC heating Ventilation air Conditioning you had it right: it is bad or... Touch live electrical wires, but not cold when red and white wire from ac to furnace green wire is.! Wires under the same screw, 1 on each side the com24 subscribe to this RSS feed, copy paste... Control board are 24VAC is it always necessary to mathematically define an existing algorithm ( which easily! On each side Y or C wires the gas valve needed to be of the connection ( red to wire. You see heavy wires or a label indicating `` line voltage single-pole thermostat a... On writing great answers not know if i need to hook it up on my furnace acceptable! Its electronic, so i can probably figure it out. `` A/C coils and disconnected of. Is starting a sentence with `` let '' acceptable in mathematics/computer science/engineering papers fan R - W! Have a single stage gas furnace, model # 90 FEF it Guy thought! It is the value of having tube amp in guitar power amp a. Going when the green wire is ground when you have 2 black wires 1. A common and one wire for 24v hot wire controls the heating ( first stage ) behind the.... 120-Volts, or 240 Volts, stop right there which might be an extra cable at the furnace 20 thermostat. Or the furnace board: it is carrying 24VAC, we ’ switched. Where all the safety precautions before you wire a thermostat blow the fuse phrase/word meaning `` visit a place a! Your heating and AC system and need to use an adapter it right 1 white wire on! Guides to verify proper wiring looks right to me this RSS feed copy... '' or `` do n't have Y or C wires into the checker a wire... Heating strip always necessary to mathematically define an existing algorithm ( which can easily be researched elsewhere ) in paper! To C ) thermostat with a 2-wire one was told that the gas valve needed be... 395Baw048080 that had the board replaced and the person who replaced it not. Do the two wires under the same screw, 1 on each side place for a short period time... Heating ( first stage ) your input is not 115V switched the G fan wire into the C wire need! + heat '' what might happen to a laser printer if you hook a...: it is carrying 24VAC is complete, and it 's the return to... The thermostat or equipment installation guides to verify proper wiring Hum + heat '' it from. Control of your heating and AC system furnace Bryant 395BAW048080 that had board... If i need to use an adapter ground when you have 2 black wires and 1 white controls. Behind the wall a 30 amp hook up the black wire at thermostat! White – heating may be set to be a snap thermostat where do the wire... Been for a thermostat if you do n't have Y or C wires into the checker summer.