Orange – This wire connects to your heat pump (if you have one). Enables continuous power flow from the Red wire. G wire (green, for a fan). 34 answer What color is the ground wire? The yellow wires terminate at your compressor contactor via an air handler. The white wire connects to your heat. In another image given below, you can see the same C wire going to the thermostat terminals side. 95 answer What is the typical size or gauge of telephone wire? Homeowners with geothermal heat pumps have no use for the orange wire. C wires are necessary for any “smart” thermostat that needs to be connected to a power source 24/7, regardless of your heat pump type. Here are common uses for wire colors: Blue or Black – C – Common wire, may be unused by your existing thermostat. Thereof, what color wire goes where on a thermostat? Orange. The Orange Wire. Remove the wall screws holding up the thermostat before disconnecting the wiring to prevent the wires from falling into the wall. by marlin | Featured, Guides |. Brown wire is used for heating elements while white wire is used for cooling elements. It terminates at the air handler or furnace. Green – The green wire connects to the fan. If you decide to get rid of your outdated thermostat for a smart or wifi thermostat, be sure to mark the wires to indicate which color letter on the board they are connected to. Thermostat Wiring and Wire Color Chart. Contractor's Assistant: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat? The yellow wire connects to your compressor. But what if you have a system that's a little different like a Heat Pump System, Then your thermostat … A majority of brands use the orange wire for the reversing valve while a small percentage use the dark blue for it. What Color Wire Goes Where On A Thermostat? When taking into consideration your thermostat wiring colors, the orange wire typically connects to the O terminal while the dark blue wire connects to the B terminal. When you set a thermostat to emergency heat, the system bypasses the compressor and directly accesses the electric heat strip. 94 answer What is the difference between CAT 5 and CAT 6 cable? The system will not operate correctly if the wires are incorrectly connected. I have a G, Y, W/AUX, R, and a loose yellow wire? The orange thermostat wire links to your heat pump, if you have one. The white wire connects to terminal W in industry-standard thermostats. Yellow – The yellow wire connects to your compressor. The white wire underneath your thermostat connects to your heating system. Red – Now, there can be two separate wires for this. For shorter runs use 20 gauge. If you observe the terminals, you can see two wires are tapped from ‘C’ terminal. Red – R – 24VAC power from the furnace's transformer. The E wire controls emergency heating. Not sure which wire goes to R and which to W on new thermostat. W wire (white, for heat). We can go from here. C wires or varying colors apply to every thermostat, but blue C wires belong to thermostats attached to a heat pump. This wire connects to your heat pump (if applicable). 18 gauge thermostat wire is recommended for any distances up to 250 feet. Thermostat wire is made of multiple strands of solid … Green. Although it may seem tedious and challenging to most, including novice electricians, completing a thermostat replacement project in your home can be quite simple. The following picture shows the inside of a thermostat. Here are common uses for wire colors: Blue or Black – C – Common wire, may be unused by your existing thermostat. These colors are used as follows: For the Y, Y1, and Y2 wires, Y or Y1 will go to the Y terminal, and Y2 will go to the Y2 terminal. Help me identify which wires go where in my Nest Thermostat? Dual transformer systems refer to a setup with a cooling and heating transformer. Orange wire and Blue wire are usually a reversing valve. Nest Thermostats, Computer or Web Browser, Google Nest Device. Here are common usesfor wire colors: Blue or Black– C – Common wire, may be unused by your existing thermostat. 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. Because many thermostats come with a pre-installed thermostat jumper wire that connects these terminals, you only need one red wire, which could be the thermostat Rc wire or the Rh wire. Multi-stage systems can require up to 8 conductors because of the amount of communication needed between the thermostat and air handler or furnace. This depends greatly on who installed it as well as who manufactured your heating pump. ( see the picture above). The green wire connects to terminal G on your thermostat. in order to know where to connect on new thermostat. What color wire goes where on a thermostat? There are many types of thermostats available today. Most thermostats have a red cable that is the power cable that usually connects to the RC terminals of the thermostat, a green cable that energizes the relay of the fan, connected to the G terminal of the thermostat, a yellow cable that energizes the contactor of the external units (if it has air conditioning) and a white cable that. Wire goes where on a thermostat to the Y terminals on your thermostat to... Health and safety are our highest priority during this time formed on end... Heat, the wires to an older Honeywell thermostat 94 answer what is the number of colored wires on new. Yellow yellow and blue electrical wires are also called “ C ” wires they! The following picture shows the inside of a thermostat systems: white refer a! 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