R: Some HVAC systems have only R wire that represents the RC and Rh wire. Without this particular wire, your Ecobee won’t turn on. Ecobee had offered several other alternative to add a C-wire to a boiler system that were a lot more complex than this option. The wire was tagged R, and we put it in Rh, the pro moved it to Rc. Helpful. Before you take a look at the next video which explains how you can easily substitute the G wire for the C wire, please be aware this works best if you have a gas, propane or forced air conventional heating and cooling system. Knowing what each thermostat wire does can help in wiring up a new or replacement room thermostat. Share. Putting more than one wire into a Nest thermostat connector can damage your system and your thermostat. Improve this question. Sometimes they are separate wires and require separate connections. So, came together quite easily. Fast, easy installation – install your ecobee in 30 minutes or less. Identify any wires label R, RH, or RC. Air or Geothermal Heat Pump with Auxiliary Heat Boiler or radiant systems Boiler or Radiant System with Air Handler and Conventional Cooling or Heat Pump Do not jumper Rc or Rh, ecobee3 does this automatically. Heat pumps R can go into either Rc or Rh terminals on your ecobee3. If you just have an R wire, it’s responsible for powering your entire HVAC system (through the use of a transformer). Follow asked Apr 2 '15 at 6:39. I connected my thermostat/furnace wires to the Rh and W1 connections and the power supply wires from this transformer to the Rc and C connections. The R, Rc or Rh wires are plugged in the Rc terminal. R, Rh, and Rc are all the same, but not. The R wire is inserted in the RC terminal of the ecobee. Heater works. 5. Thermostat wire reference chart: this article explains just what wire at a room thermostat actually controls. Aside from the RH and the RC wires, there are other wires that you will find in your cooling or heating system. HEAT PUMP (AIR OR GEOTHERMAL) … Do I answer that yes that's correct and the ecobee will make the jumper Instaledl Nest for my millivolt heater Published on January 15, 2019 by Kindle Customer I live in an old San Francisco Victorian. The RC terminal is the 24-volt cooling power supply. Rc G Y1 Y2 O/B PEK ACC-ACC+ W2 W1 C RH Y1 Y2 C Y1 Y2 W1 W2 R C G WIRING DIAGRAM Conventional heating and cooling (up to 2 stages each). Air Conditioner Furnace Stage 2 heat and cool, if applicable NOTE Do not connect any jumper wires between Rc and Rh. White wire to W. This wire switches the heater on and off. Before fixing the back plate to the wall, cross-check the connections. The fan pushes cool or hot air through vents into your home. The Rh wire, another type of red wire, is also responsible for 24-hour volt power from your transformer. C wire, which is the abbreviation for the common wire, is the primary wire that enables the ecobee thermostat to operate. BUT, the smart tstat needs a 12v power source at some point, so there need's to be a + connection, which I believe should be at the C terminal. It’s not a live wire, but it does operate the blower fan. They provide a source of 24V power coming from the HVAC control board. Be sure to insert your R/Rc/Rh wire in the Rc terminal of your ecobee3 lite thermostat. This wire may be red without an “H” attached to it, depending on if you have a dual transformer setup. Please refer to the owner's manual of your old thermostat for clarification. Black wire to C. This wire provides the return path for the power that flows through the red wire and through the internal circuitry of the thermostat. My house was built in 1996 and the Air Handlers and Furnace are original and nearing EOL. Do not connect any of the wires to Rc on the new thermostat. ** The common wire could be labeled "C" on your old thermostat, or it could be labeled "B" or "X". Improve this answer. I have seen guides that you can get a transformer and connect to C and Rh or Rc. If you accidentally clipped the RC/RH jumper on the back of the Sensi thermostat and did not mean to, you will need to re-jumper those two terminals. ecobee does this automatically. If you do have an Rc and an Rh wire, the Rc wire is the power wire for your cooling system. So, hooked up external transformer and connected to C and Rc. The red wire controls the main power switch for the heater and the cooler. This indicates you have a two-transformer system. The Ecobee3 connects the Rc and Rh terminals automatically which means you can choose either Rc or Rh to plug the wire into. hvac thermostat. Report abuse. 1. R, Rh, Rc: Your system may have just an R wire, an Rh and an Rc wire, or a lone Rh or Rc wire. 65 1 1 gold badge 1 1 silver badge 5 5 bronze badges. A/c does not work. Typically, the wires that provide the power (often called the “hot” wires) are labeled R c (cooling) and R h (heating). my old thermostat jumped Rh/Rc. I have used the Fan only mode previously and so I don't want to sacrifice my G. Additionally, I do not see a place on the Air Handler to run a C wire. I'm certainly not an HVAC guy, or an electrician. Ended up getting a Honeywell RTH6500 from Amazon vs Ecobee. It connects your heating and cooling system to the common ground and provides power to your thermostat. * If the old thermostat has separate RC and RH wires coming out of the wall, clip the RC/RH jumper on the back of the thermostat above the battery compartment. Green/G – controls your fan. Clip the RC/RH jumper wire on the Sensi thermostat if you have two separate wires (one running to RH and the other to RC) on your old thermostat that are coming from the wall. In that case it will typically be labeled R h/c. If I can, which of the two should I use? The RH terminal is the 24-volt heating power supply. Do not jumper Rc or Rh, ecobee3 does this automatically. Instead, a short jumper wire connects two thermostat terminals together. If you just have one wire, regardless if it's labeled RC, it will go into the R terminal, and the jumper connecting terminals R and RC will be in place. I have a CT100 thermostat running on batteries since I do not have a C wire. The W or W1 wires are finally connected to the W1-terminal. White/W – controls your furnace. I know that the Ecobee it's not necessary to jumper that as the thermostat does it automatically.. my question is that when it states we have detected a wire connected to Rc but not Rh. Removed jumper between Rc and Rh as suggested by Bill Lee below. OLD Thermostat: G – G wire, W – W wire, Y – Y Wire, Rc + Rh (R wire with jumper between Rc and Rh) New Thermostat : needs a C wire. Now connect the red wire from the boiler into the RH slot and your white wire into the W1 slot. 5.0 out of 5 stars It Worked! Currently the ground wire is going to Rc/Rh. AwesomePossum AwesomePossum. The wiring part is easy as pie. Should be good to go on connecting the black wire to C on your new thermostat. This data can also be helpful if thermostat wires have become mixed-up or improperly color-coded by allowing you to trace wires back to their control connection point. The RC wire (C for Cooling), if connected properly, controls your HVAC cooling. RH and RC are wired separately for power if you have a two-transformer system, where there are separate transformers for cooling and heating. I'll test it prior to hooking into the system to make sure it runs before going any further. My house has separate heating and cooling so I have 5 wires in total. The RH wire (H for Heating) provides power to your HVAC heating. Luckily, for … Read more. Due to old heater panel, I could not find the C wire to hook up. Nest thermostat connectors are built so that only one wire can be inserted into each connector. I hooked up the transformer wires to C and RC and the heater wires to W1 and Rh. R wire to Rc terminal (PEK installs must use the Rc terminal) G wire to G terminal ; Y wire to Y1 terminal; W wire to W1 (Aux1) terminal; Again, my wire colors in this photo happen to match up, but make sure to attach the appropriately labeled wire, even if it’s not the matching color. Can I still get a transformer and then use Rh or Rc? Rc wires connect to the RC terminals on your thermostat. After that, connect the non-stripped wire into the c slot. Here are some of the most common wires and what they signify. Reply. The G-wire is plugged into the C-terminal. Substituting a G Wire for a C Wire As you will notice from the information above, your ‘G’ wire connects to the fan (as industry standard) and is green in color. The Rh Wire. You will typically have one or two out of those three. Double-check your connections and then finish up by affixing the backplate to the wall. In … Two thermostat wires that are critical to the operation of the thermostat are the RH wire and the RC wire. The Rh wire connects to your heating system as opposed to your cooling system. The Y-wire is connected to the PEK terminal. On page 29 of the instruction manual, it says, “Do not jumper Rc or Rh, ecobee3 does this automatically. Blue or Black/C – a C-Wire or a common wire. It works perfectly...so far. G. The G wire is probably the safest wire in the unit. Dumb question. Once you’re done, you can see your Ecobee thermostats up and running. I'll update if it fails in the next year. That means I currently already use Rh and Rc. Rh: Rh wire is used as the power wire for both cooling. This is fairly common on the Rh and Rc terminals.. Nest thermostats don't use jumper wires . The thermostat wire is color coded so the technician can identity which wire goes to which port on each board. The following wiring diagrams are for the ecobee3 thermostat and common HVAC equipment configurations. First, from your AC adapter, you connect your Striped Wire into the RC slot and connect your non-striped wire into the C slot. For homes that lack a common wire, a range of solutions are available, ranging from the practical to the rather risky. Though, this common wire can also be abbreviated as X or B wire. Other times they are the same wire. In this case if Rc were shunted to Rh it would pop the overload protection on the furnace board or the transformer. What To Do If You Don’t Have A C-Wire. Yellow wire to Y. In this guide, I will be explaining one of the easiest and cheapest methods to get your Ecobee Thermostat up and running in the absence of the C Wire. This video refers to connecting the other external transformer wire to an "Rh" terminal and I am confused. R in general. For those in a hurry, all you have to do is purchase a C wire adapter and connect it to the terminals for your Ecobee thermostat. Check there for a wire running to the “c” terminal to confirm if you have an existing c wire. R can go into either Rc or Rh terminals on your ecobee3.” Ecobee provided the following defense in response to our frustration, “As far as the system sending notifications it does send them. It also means. The best all-round solution is to add a c wire to your home. This was the easy fix 7 people found this helpful. Edit: Schematic for Goodman AMV9/ACV9_XA furnace:  Share. Ecobee support tells me the PEK is not an option. In a 4-wire system jumper them together or you won't get both heat and cooling. You'll need a 5-wire thermostat cable to wire your new thermostat. Now, connect the red wire from the boiler into the RH slot and the white wire into the WI slot. Adding A C-Wire. Add a comment | 1 Answer Active Oldest Votes. W is your heating terminal, and normally will have a white wire. I'll definitely get an EcoBee for home, but during the project I found that the hot lead coming off the DuoTherm was only 7.5V which wasnt enough to power an EB. Red wire to Rh or Rc, which are usually bonded. These diagrams are also available within the ecobee3 Installation Guide included with your ecobee3 thermostat. But I already have something in RC? In your case, they need to be jumpered as you only have a single transformer. Please help Bill Lee. What are my options? Erich Leyendecker. This completes the wiring stage of the installation. The R wire needs to go into the Rc terminal on your ecobee. So, ended up getting a cheaper Wifi Tstat (the Honeywell), and bought a 24 VAC transformer, and 3 x 90-290Q relay switches. Don't jumper them in a five-wire heat/cool system, the thermostat will select the correct power source depending on whether it is cooling or heating. It’s important to note that in some cases the color of the wire does not necessarily mean it connects to that came color one the board.