Thermostat No Yellow Wire

Thermostat Wiring Chart There is no official standard for wiring colors, or even terminals for that matter. We've partnered with HomeAdvisor to bring you instant access to a nationwide network of installation pros who can get you set up right away. A thermostat turns your furnace and air conditioner on or off depending on the temperature in the room and the setting on the thermostat. Thermostatic Wiring Principles by Bob Scaringe Ph. It uses the same color-coding as the 5-Wire thermostat except they don’t have a cooling wire. Red - Now, there can be two separate wires for this. Is the thermostat bad or just as wire problem?? It has the Duo-Therm thermostat with a 4. How come there were no wires coming out of the back of the thermostat? I need to know where to connect the thermostat wires from the wall. Even if you’re keeping your Nest Thermostat, but are simply just moving it to a new house, you’ll still need to factory reset it, since the Wi-Fi network will be different, and more importantly, the heating and cooling systems at the new house might be different from what your Nest Thermostat originally had set up. Press MATE twice. Either an extra usually red wire will connect to the “RC” terminal, or there will be a jumper wire in the thermostat connecting “R” to “RC”. Hi My Name Is Lindsay And Im Having Trouble Installing My New Honeywell thermostat:o it's a non digital thermostat, round one the old fashioned kind, I don't know where to connect which wire because I don't know which wire is which I have the following wires. But you didn't say that. W: White, controls the heater ; Y: Yellow, controls the AC compressor. The best furnace thermostat wiring Exclusive coleman evcon furnace wiring diagram. Air conditioning thermostats wire are color coded in white, yellow, green, red, and (C) common wire. lug shows as going to the yellow on the thermostat. My old thermostat had the yellow wire connected to both the yellow and white terminal. Wiring must comply with local. R - No wire attached. Use one of the existing wires on the thermostat to connect to the proper end on the male terminated yellow wire. Ensure you also connect the green wire to the fan relay and further connected to the G terminal on the thermostat. Y - Yellow wire attached. C is known as the common terminal. The O wire. Call 1-800-468-1502 for wiring assistance before returning the thermostat to the store. Thermostat with 4 wires, red, green, white and blue; no yellow wire to connect to new thermostat I have an old mercury thermostat [Lennox/white Rodgers P/N 32M7601, Type LR27935 class 2 1F56W-92], and I purchased a Lennox Comfortsense 3000 non-programmable digital thermostat [Model No. My wiring was as follows: yellow wire (always A/C) to Y. This is a picture of the thermostat wiring. I decided to install a Honeywell RTH6350 programmable tstat on both units. For the record, it’s my kryptonite. The place I recently moved into has a 4-wire thermostat installed, but there are also two unused wires at the thermostat (one brown, one blue). If there is a call for cool, R is connected to Y (compressor). When I removed the old thermostat, I notice that the old thermostat connected with red and white wire only. Types of Thermostat Wire. The first thing you should do is check for any loose wires. Smart Thermostat Wiring. Sort By Show. Remove existing thermostat from the wall to expose the wiring terminals. the 3 going to the central air are Y,Rc,G. 2 Wire Thermostat Wiring Diagram Heat Only Book Of Nest Wiring - Nest Wiring Diagram With Heat Pump. (Heat) For example, if you want to turn the fan on, power flows from the red (R) wire to the green (G) wire. Always refer to your thermostat or equipment installation guides to verify proper wiring. How to Install and Set Up the Nest Thermostat Craig Lloyd @craigelloyd November 1, 2016, 10:08am EDT A smart thermostat is a great accessory to have, not only to be able to adjust your home's temperature from your phone, but to also save money on your utility costs. I searched the Internets for old manuals and anything that might help. We do not cover 110/240-volt thermostat wiring and millivolt thermostat wiring issues. Thermostat wire color guide Colors and their usages vary by system and installation - there is no standard, and furnaces/thermostats don't enforce the usage of one color over another. Red wire goes to Rh or Rc, with the two terminals usually bonded. If your old thermostat didn't have a "C" wire connected, but you have an unused wire in the wall that you could use as a "C" wire, label everything and skip to Step 4-and-a-half. I'm confused about this blue wire connected to the B terminal. 4 Wire or 5 Wire Thermostat Wiring Problem - Question: We have a 19-year-old condo with an old Carrier mercury thermostat. You can power each security camera with its own plug in power supply, or you can wire multiple security cameras back to a multi-camera power source. The charged NEST works without the connected common wire. Older models did not need C-Wires, so the reason your thermostat isn’t working is because your system doesn’t have one, at least not yet. Whichever wire matches the color, should be your c wire. But you didn't say that. Furnace Fans furnace thermostat wiring diagram. A new message and message archive with a few repair notes Please use this site to assist you in troubleshooting most geothermal heatpumps. We have both a natural gas furnace and an AC unit. Some thermostat wires that coming from the air conditioner unit with four wires and there is no common wire. G - Fan (green wire) R - 24 VAC / Rc and R or Rh (red wire) Y - Compressor / air conditioner (yellow wire) W - Heat (white wire) Note: A previous installer may have used a different set of color wires. Wiring an air handler thermostat is a relatively straightforward task. All wiring must be done in accordance with local code. POST a QUESTION or READ FAQs about what different thermostat wires actually do - what each wire controls is given in this standard thermostat wiring chart. Thermostat Wire Found (31) Items SEARCH. W: White, controls the heater ; Y: Yellow, controls the AC compressor. yellow wire to the Y terminal following. Some Carrier thermostat systems also come with a “Constant ON” feature. There are a couple of options available to create a C wire and make the ecobee compatible. I'm guessing these are probably low voltage thermostat wires that come from the heater, and not from a power source. My existing wiring is only four wires: green, red, blue and white. They would talk about furniture that people would want to spend all of their days in. View and Download White Rodgers 1F79 installation instructions manual online. Connect to your Nest Learning Thermostat and Nest Protect smoke and carbon monoxide alarm from one place - the Nest app in your web browser. Red: Connect to the red wire of fan pigtail with pre-terminated yellow crimp. Hi Dfour! I am sorry, but I have no idea what the yellow wire to 1 is for. I've learned how to get to a few more parts on the car, without breaking anything or wasting money on unnecessary parts, which I really hate to do. Always refer to your thermostat or equipment installation guides to verify proper wiring. (Fan) Y terminal will use the yellow wire. The relays in turn switch on the power to the fan and the air conditioner or furnace. 4) Unit running backwards or Unit runs both heat and cool at the same time P274-XXXX Series Cooling on heat demand, heating on cool demand - the heat pump wiring is wrong. When I removed the old thermostat, I notice that the old thermostat connected with red and white wire only. I am about to replace my current Room thermostat with a new Honeywell CM907. I have a 3 core mains cable (red yellow blue) and 4 connectors (nubered 1 to 4) in thermostat. (Air conditioner) W terminal will use the white wire. The main difference setting each apart is the number of colored wires. Before you buy a replacement thermostat, however, take a peek at your existing wiring. View full product specs online from Allied Wire and Cable for more info. And there is no assured way to say the the installer followed the standard color code wiring in the first place. Red – Now, there can be two separate wires for this. I was lucky that my thermostat wiring contained an extra, unused (blue) wire, and my furnace's control board provided a 24VAC common terminal for a "C" wire. You can use a short piece of wiring with the ends stripped away to create a "jump" between connections. I have purchased the Horstmann DRT2 digital thermostat off Screwfix. The two transformers provide the power the thermostat uses to switch on the various relays. W - White wire attached. Belden® provides high-quality, top performance, and total reliability. Before I call in a pro to check out the system can anyone tell me how I should have wired the thermostat for the heat pump. Currently I have three wires going into my old thermostat Red, Blue and Yellow. (The other yellow wire was joined with other zone valve yellow wires and was connected to a wire going to one of my transformers on the opposite side to the load side on that transformer and thus not helpful. Switch your stat down to zero - the boiler shouldn't fire; then move it up to around 30 and it. Belden Wire & Cable Products – Cut by the foot. Wiring Chart Label Old Thermostat Typical Wire Color Description HUM Humidifier NC Not used W2/E Brown 2nd stage heat W1/ O/B White/ Orange/ Blue 1st stage heat/HP reversing valves RH Red Power from heat, 24VAC transformer RC Red Power from cooling, 24VAC transformer Y2 Gray Stage 2 compressor relay Y1 Yellow Stage 1 compressor relay. These cables are also suitable for use in annunciator and bell systems, remote control units, signal systems and other low-voltage installations. Proper electrical wiring and cable ensures that you'll be able to safely power all of your household devices. Verify thermostat and system wires are securely attached. Next I attached the yellow wire coming from the transformer to the yellow wire running down from the thermostat. Trying to wire up a new Drayton RTS2. I followed the directions and wiring digrams for both. RV Products suggests the thermostat wiring be a minimum of 18 gauge. This wire pair is simply a wire splitter, where a blue wire is splitted into yellow and green wires. No, no, no! It'll go bang! Old mechanical thermostat's needed a neutral connection to increase accuracy. Replacing a 3. There were no connections on the new thermostat for him to wire. Learning thermostats like the Nest help keep your home comfortable and can save you money on your energy bills. I don't know the common colors, so I can't tell you what colors do what. At Honeywell, we're transforming the way the world works, solving your business's toughest challenges. Check out the Ct100 no AC you should be fine without the yellow. Full-featured devices like the Prestige need power from a third wire, something best installed by an HVAC or electrical contractor. She just cut her electricity bill to 60%, click here to read. New two wire digital stats do not require this neutral connection so leave the wire disconnected and tape it up for protection. The thermostat wire will connect to a terminal strip on it. I am about to replace my current Room thermostat with a new Honeywell CM907. If all the wires are in the correct place, the next step is to see if you mistakenly installed a four wire thermostat to a five wire base. Switch your stat down to zero - the boiler shouldn't fire; then move it up to around 30 and it. Thermostat wire is designed for thermostat control, heating and air conditioning installations, touch-plate systems, burglar alarms, intercom systems and door bells. Security cameras can be powered two ways. An R wire can go into either Rc or Rh. The three wires are red, white, and blue or yellow, depending on the manufacturer. Thermostat Wiring and Wire Color Chart – Thermostat Wiring Colors Code; Tstat Terminal Designation: Color of Wire and Termination: R – The R terminal is the power. The most common is 18/5 (5 strand, 18 gauge). Tips On Saving Energy Thermostat Troubleshooting Yellow Black Cossette Hydro One Welcome Kit air furnace service switches look like wall light switches and are located at or near this condition, please call your HVAC service company as this is likely a furnace problem, not the thermostat. When this is the case, you should immediately remove all wires since it can cause damage to the entire system. If you have a fan relay, it will likely be marked G and be green. Bundle #1 red to bundle #2 red. If there are only two wires, the simplest solution is to get a replacement with a battery-powered display. Note: Pull the thermostat wires out as far as possible. C is normally the common wire to the transformer, normally a brown wire. Gray: Connect to thermostat socket (sending unit) with blue ring crimp connector. I followed the directions and wiring digrams for both. Trying to wire up a new Drayton RTS2. (Fan) Y terminal will use the yellow wire. In stock and ready to ship. A thermostat turns your furnace and air conditioner on or off depending on the temperature in the room and the setting on the thermostat. From what I read, B & O. I could REALLY use some guidance as to what three terminals on the new thermostat I should use to connect these three wires. These two connections will ensure that there is power to the. You need two wires to complete a circuit - voltage and a return path. Last time I used the Hunter 42999B; that model is no longer available, so this time it'll be a close copy - the Supco 45034. 2) Display goes blank or shows "PF" when starting cooling or heating - The thermostat only does this when there is no common wire. The relay for the electric heat or the gas valve, on the other hand, is connected with a white wire. right now you are using the green wire as a common ©. If your old thermostat didn’t have a “C” wire connected, but you have an unused wire in the wall that you could use as a “C” wire, label everything and skip to Step 4-and-a-half. How to start an AC unit when thermostat is missing the Yellow wire is Compressor. I have seven wires Blue (C) Yellow (Y2) Green (G) Red (R. Not only does it let you control temperature easily, the unit will also be able to find out your routine. The black/blue wire goes to C. Y - Yellow wire attached. The current thermostat is Indiglo 43154A and the HVAC is Trane 4TCY-IG-8 Single packaged, cooling with electric heat. This shows where to hook them up in a typical heat / cool setup. The voltage on the Green wire is varying and when it gets down to 18VAC the blower fan kicks off. The most common is 18/5 (5 strand, 18 gauge). ran new ground still no power to relay out of yellow wire that comes down from switch in coach alli can think of is a broken yellow wire unless there is something between the on switch and the relay at the tank any help please wally#2378 04 seeya. Red - Now, there can be two separate wires for this. The question I have is what thermostat do I need (if the new ones have W1 Y1 terminals and currently my wiring is as described above). Red/R* - power wire for your heating and cooling. Find multi-conductor, paired, coaxial, flat and fiber optic cables, plus portable cordage, molded cable assemblies, hook-up and lead wire. The first thing you should do is check for any loose wires. Just as a side note here, the CAT5 has eight cables, but not all wires need to be used. I have red, blue and yellow/green wires from the old thermostat. RC - Red Wire (Power 24 Vac) RH or 4 - Red Wire Jumpered (Power 24 Vac) W - White Wire (For Heating Enable) Y - Yellow Wire (For Cooling Enable). Green - The green wire connects to the fan. The accessory can also be used for fixing a broken wire, to make one thermostat work like two, to add cooling to a heat-only system, or to add a common wire to a 4-wire system. Standard Wire & Cable Company can supply you with the right sizes, types, and quantities of product you need to keep you on schedule and your management happy. In case of removing the old thermostat be aware that the existing wiring will no longer be used. NOTE Some AC Systems will have a blue wire with a pink stripe in place of the yellow or Y wire. A thermostat's terminals are marked with "Y," which is usually a blue wire, "W" is a white wire, "G" is typically black, and "R" is red. The Google Nest thermostat detects wires by testing them in two ways: mechanically (is a wire inserted?) and electrically (is there an electrical signal on the wire?). Expected a 5 wire system. This diagram is to be used as reference for the low voltage control wiring of your heating and AC system. In common with most coach accessories in an RV, the thermostat that controls the air conditioner (AC) is a regular household unit. Make sure you put it on the correct terminal. The most common is 18/5 (5 strand, 18 gauge). If the switch is tilted to the right (as it would be if the air conditioning were on), the current travels through the mercury into the blue wire. There may be up to a five minute delay before the thermostat clicks in Cooling. Make sure all connections are tight so that electricity runs properly through. A thermostat turns your furnace and air conditioner on or off depending on the temperature in the room and the setting on the thermostat. Do not remove any wires from your thermostat at this time! 75 75 OFF OFF ON OFF OFF ON Breaker box Switch 4 Make sure there are no 120/240V wires. Typically, a furnace plus A/C HVAC system has four or five thermostat wires and a common wire. The W (white wire) is for the heat. We installed our 2nd Nest last night. The obvious down side of this is that if the battery goes dead the thermostat will no longer function. I'm confused about this blue wire connected to the B terminal. Bundle #2 yellow to thermostat yellow. • Red wire (labeled "TO T-STAT +12 SCREW) for voltage ranging from 6. It connects to the pink wire, which leads to the bottom wire in the mercury switch. Thermostat Wire Reference Chart List of the control function of each ID label or color of room thermostat wires. A C-Wire enables the continuous flow of up to 24 VAC power from your system to the thermostat. Check out the Ct100 no AC you should be fine without the yellow. Yellow to Y1 Make safe bare ends of blue and earth and tuck out of the way, as not needed. • If there's a white wire in the connector labeled both W and O/B, then you probably don't have a heat pump. The Hive Active Thermostat can be self-installed, but if you need a little help we've got you covered. the 3 going to the central air are Y,Rc,G. bk-2 thermostat bk-1 bk-2 bk-3 mgt thermostat bottom bk-4 thermostat bk-3 gy-26 bk-24 hood thermostata og-27 wh-31 yw-32 door sensing switch yw-6 yw-7 primary switch bk-4 bk-8 monitor switch wh-11 wh-9 gn-28 yw-29 motor condenser bk wh bk wh gnd noise filter bk-1 wh-12 out in bk wh power cord wh-11 bk-10 wh-9 bk-8 h. If all the wires are in the correct place, the next step is to see if you mistakenly installed a four wire thermostat to a five wire base. Hi all, I purchased a Honeywell wireless thermostat (RTH8580WF) that requires a c-wire connection. Questions about the C-wire are by far the biggest drivers of traffic to this site, so I've written this article to. Wiring Guide for a Honeywell Thermostat Electrical Question #1: How do I connect the wires for a heater thermostat? I bought a Honeywell Heating thermostat. G - Green wire attached. Whichever wire matches the color, should be your c wire. Put this wire in the Nest Thermostat’s W connector. The coil ohms good at 16 ohms, the thermostat is shorting the red to the yellow and green (fan) wires (measured at the furnace), furnace fan is a no go and the compressor is not starting. 1F79 Thermostat pdf manual download. Note that the wires should be screwed to terminals marked R (red), W (white), G (green), Y (yellow), and C (common). In case of removing the old thermostat be aware that the existing wiring will no longer be used. In stock and ready to ship. If the equipment is a heat pump, or heat only or cool only, you MUST have a common wire. The thermostat wiring is factory installed by the OEM (Original Equipment Manufacturer). I currently have a Robertshaw 300-208 thermostat running my Luxaire heat-pump and (some other brand) electric furnace as auxiliary heat. They are R, W, G, B but all the instructions show 5 wires. I am trying to install a RTH2300B thermostat to replace my old thermostat…. Seems like W2 is for heat relay 2, but on the old one there is no W1 for heat relay 1 I don't know what kind my system is (2h/2c, 2h/1c etc) i was hoping to figure this out from the wiring The wiring on the old one: W2 - white E - blue C - black Y - yellow G - gren R - red O - orange. So the G wire here does control the HVAC fan. I do not have six wires going to the existing thermostat - I have only three. In case of removing the old thermostat be aware that the existing wiring will no longer be used. Insteon 2441TH Thermostat Wiring. After hooking up the blue wire at the furnace and the Nest's base, I now seem to have successfully provided a 24VAC "C" wire to the Nest, and hopefully my battery issues are behind me. In addition there should be a wire to tell the AC unit to run. One way to test thermostat wires--on your heating system, for example--is to disconnect the wires from the thermostat and transformer, wire them together at one end, and test for continuity at the other end by clipping a continuity tester to one wire and probing the other wire. Thermostat Installation & Wiring Diagrams; 3-wire heat-only thermostat (R, G, W) If you have a heat-only system, you may notice that your thermostat has three wires—R, G, and W. Note: Pull the thermostat wires out as far as possible. You will need to correct the C wire issue to get the yellow light to blink If the C wire is working correctly and you still do not have a yellow light - try the following Preform a reset to. Now, my particular furnace controller board does not have a 24 Vac, “C” terminal (some do, some don’t). thickness inches mm inches mm nominal. How to Wire a Thermostat. So the G wire here does control the HVAC fan. I was lucky that my thermostat wiring contained an extra, unused (blue) wire, and my furnace's control board provided a 24VAC common terminal for a "C" wire. Four Ways To Fix the C Wire Problem. The "C" wire is a powered wire that supplies 24VAC to your thermostat. Wiring Diagrams - Carrier Wiring Diagrams INDEX MODEL NO. Unit provided heat when compressor outside kicked on. Honeywell thermostat wiring diagram 4 wire. I stripped the ends of both about 3/4", used pliers to wrap the wires around each other in a clockwise direction and secured them with an orange wire nut. If there are no screws, then use a flat screwdriver to remove the cover. Making a Nest thermostat work with a two wire system in AC mode Post by malcolmh » Tue Jun 06, 2017 5:49 pm OK - so I have a zoned house (3 zones) and the 2 wire solution worked great for me during the winter with a Nest thermostat in each of two zones and a "dumb" thermostat in the 3rd zone. Red wire goes to Rh or Rc, with the two terminals usually bonded. I have seven wires Blue (C) Yellow (Y2) Green (G) Red (R. These two connections will ensure that there is power to the. Clear List. Thermostat has not yellow wire, AC not working 1 Recommended Answer 3 Replies 1 Upvote. The thermostat I got has a o/b, y, r, g, and w. Wiring an AC thermostat becomes necessary when a remote. See Page 8 for the Gen II Mini. I have 2 Rheem heat pumps in my home that had regular mercury type thermostats. "I see that you sell tankless instantaneous gas and electric water heaters. Wiring Guide for a Honeywell Thermostat Electrical Question #1: How do I connect the wires for a heater thermostat? I bought a Honeywell Heating thermostat. What am I doing wrong?. Red wire goes to Rh or Rc, with the two terminals usually bonded. The best way to figure out if you need to adjust to a c-wire system is to take your thermostat off the wall and see what it looks like. I need to use a c wire. No sound from the handler and no air blowing from the vents. Hi, I was going to replace my 3 wire room thermostat with a 2 wire digital one Honeywell DT90E, a quick google tells me this should be easy and I should take the red wire from terminal L in my. The basic Heat + A/C System thermostat typically utilizes only 5 terminals. Electrical Wire and Cable Bring Power and Data to Your Home. Any suggestions?. Related Posts. Insteon 2441TH Thermostat Wiring. This is an older gas forced hot air heating system, with no central AC. I am going to replace to my old honeywell thermostat ( has mercury vail in it) to a RiteTemp digital thermostat. If you jump (connect) the R -red and Y-yellow the compressor will turn on. POST a QUESTION or READ FAQs about what different thermostat wires actually do - what each wire controls is given in this standard thermostat wiring chart. The "C" wire is a powered wire that supplies 24VAC to your thermostat. This is a common problem when replacing a mechanical thermostat or a thermostat powered by batteries. Get free 2-day shipping on qualified Thermostat Wires products or buy Electrical department products today with Buy Online Pick Up in Store. I have purchased the Horstmann DRT2 digital thermostat off Screwfix. I have 2 units in a multi zone system, i. This complete 24-volt thermostat wiring guide covers all thermostat wiring issues from the simple to the complex. 3 wire dryer power systems are for use with existing ungrounded dryer receptacles mainly in older homes whose wiring in years gone by was not grounded. The most common need for additional wiring when installing an ecobee comes from the lack of a C wire. If the common wire is present, check it for continuity, look for a short, a broken wire, or a bad connection. RC - Red wire attached. Some shorts are direct shorts, which commonly causes a fuse in the furnace to open. T28 Fan Coil Thermostat Installation Instructions 3 Wiring Make wiring connections using wire nuts or other approved solderless connectors. The work I've done so far is not a waste. G - Green wire attached. Find Thermostat Wire related suppliers, manufacturers, products and specifications on GlobalSpec - a trusted source of Thermostat Wire information. You should now just have your thermostat wire bundle sticking out of the wall, like this:. We have both a natural gas furnace and an AC unit. Yellow (Y) usually controls the air conditioner's contactor. NOTE Some AC Systems will have a blue wire with a pink stripe in place of the yellow or Y wire. The G (green wire) is for the blower fan. Wiring Diagrams - Carrier Wiring Diagrams INDEX MODEL NO. Belden Wire & Cable Products – Cut by the foot. green from #2 bundle to thermostat green. Many thanks. Cool terminal on thermostat. How to Wire a Thermostat. Problem Solution ; If the Nest thermostat isn't getting enough power from W or Y and there is no Common wire: While we find that in the vast majority of homes the Nest Thermostat can charge its built in battery by power sharing from the regular heating and cooling wires. Tips On Saving Energy Thermostat Troubleshooting Yellow Black Cossette Hydro One Welcome Kit air furnace service switches look like wall light switches and are located at or near this condition, please call your HVAC service company as this is likely a furnace problem, not the thermostat. C is normally the common wire to the transformer, normally a brown wire. Honeywell thermostat wiring diagram 4 wire. Wiring: Mount the relay in a secure place in the engine compartment away from heat sources. Thermostat Equipment HVAC System Green Y ellow White Purple Brown Red Black Factory Link Relay Common Sender Receiver / Relay Module Base Logic 70mm 30mm 18mm 9mm 10mm 86mm Smart Temp Smart Wire Module 2 to 5 Wire Adaptor www. How to set up your ecobee. Since one of the two white wires was being used as a yellow wire, I assumed it should be hooked up that way on the new one. Four wires come to the centrally-located thermostat from the main heating/cooling unit (usually located in a closet, basement, or occasionally in the attic): One wire, usually red, supplies 24 volts AC power to the thermostat, while the other three supply control signals from the thermostat, usually white for heat, yellow for cooling, and green. The RC and R terminals are jumpered (as part of how the thermostat is manufactured). Orange – This wire connects to your heat pump (if you have one). Replacing a 3. 2 Wire Thermostat Wiring Diagram Heat Only Book Of Nest Wiring – Nest Wiring Diagram With Heat Pump. Y - Compressor, usually a yellow wire W - Heat, usually a white wire The thermostat is a set of contacts where G, W and Y are connected to R based on the following rules. In common with most coach accessories in an RV, the thermostat that controls the air conditioner (AC) is a regular household unit. All these wires will need to be plugged into the corresponding terminals on the inside of your thermostat. Thermostat Wiring and Wire Color Chart. After hooking up the blue wire at the furnace and the Nest's base, I now seem to have successfully provided a 24VAC "C" wire to the Nest, and hopefully my battery issues are behind me. The Y (yellow wire) is for the compressor and outdoor fan motor. note: plumb humidifier to hot water when using this wiring configuration. Rated 1 out of 5 by Hawk from Honeywell thermostat I have a two zone forced hot water system for my home and replaced the old mercury style thermostats with these new ones. You can power each security camera with its own plug in power supply, or you can wire multiple security cameras back to a multi-camera power source. 3 Welcome! If your old thermostat has 110/120V wires capped with wire nuts, it is a high voltage system and is not compatible with your ecobee3. Rheem Heat Pump thermostat Replacement. If there is no wire, you don't have a c wire and will probably want to get one. Thermostat Wiring Color Code. I'm going to assume that the 3 wire bundle is from the furnace, and the 5 wire bundle is from the a/c. I decided to install a Honeywell RTH6350 programmable tstat on both units. Whether the thermostat is being wired as a single-pole or double-pole, both the black and white wires are hot in any 240-volt circuit. Red wire goes to Rh or Rc, with the two terminals usually bonded. Please note that the green and yellow wires of the Diode "Y" may not be connected to the R or C terminal of the thermostat. Press tabs only to remove wires from terminal block if necessary. If you have a fan relay, it will likely be marked G and be green. So you’ve decided to install your new thermostat and discover that you have an unused wire but you do need a C wire connection. Not only does it let you control temperature easily, the unit will also be able to find out your routine. The Y and Y2 wires are most likely yellow ones. The red wire is connected to terminals beginning with the letter R, which include R, RH, and RC units, depending upon how the thermostat is being used. Match equipment letter terminals to corresponding Honeywell RTH7500 letter terminals. Is that too over-the-top? Perhaps so! However, if you yourself are looking for a timeless piece of classic furniture, a grand piece that stands on four feet, look no further than the Quitaque Chesterfield product by Greyleigh. Verify thermostat and system wires are securely attached. No C wire in this example. THERMOSTAT YELLOW 3 existing wires with Add-A-Wire™ to add cooling to a system that already has heating.