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A thermostat is a switch that can automatically turn on a furnace when a set temperature is reached. The two 24 volt wires go to the R terminal and C terminal inside the thermostat. Furnace 24 Volt Transformer. R is the hot side, while C is the common side of the transformer.
Where do the wires from the thermostat go?
The white wire underneath your thermostat connects to your heating system. It terminates at your air handler or furnace. The white wire connects to terminal W in industry-standard thermostats.
What color wires go where on a furnace?
This is the most typical thermostat wiring style, and it applies to systems that regulate both heat and air conditioning. The wires are typically arranged as follows: red for 24-volt hot, white for heat, yellow for cooling, green for the fan, and blue for common (although the common wire may be a different color).
What are the wires on a thermostat?
Thermostat Wiring Tips The W wire is connected to your heating system. The Y wire is yellow and connects to your air conditioning compressor. The G wire is green and connects to the fan. Rc and Rh: The red wire(s) are the power source for your thermostat.
What happens if you wire a thermostat wrong?
Potential consequences of improper installation could include: Electric shock. Blowing a circuit breaker. Damaging the thermostat unit, the electrical system or even the AC/furnace unit itself.
What kind of wire does a furnace thermostat use?
The most common thermostat cabling is 18/5 (18 gauge, 5 conductor), because 5 conductors typically offer enough functions for a modern thermostat/low voltage device.
Where does the black wire go on a thermostat?
More often than not, the black or blue wire connected to the C terminal is found in the newer “smart” thermostats. The older thermostats may not have the “C” wire; they function on-demand while the new ones function all the time (continuously 24/7).
How do you identify thermostat wires?
Look for connectors that have labels that are the same as your thermostat. For instance, you might find labels like R, W, G, Y, C or O/B. You should find wires attached to these connectors that are the same color as the wires that connect to your thermostat.
How do you connect 4 wires to 2 wires?
The first option is to use the black wire of the 12-3 cable as the hot wire. Connect the black wires of both cables together, and connect the common white wires together. Cap the red wire and leave it untouched in the junction box. Place plastic twist caps on all splices.
What color wire goes where on a Honeywell thermostat?
Meaning of Wiring Terminal Letters W (white) controls the auxiliary heating elements. Y (yellow) controls the compressor on the cooling system. G (green) controls the fan. C (blue or black) provides a return path to the transformer.
Does thermostat need jumper wire?
Nest thermostats don’t use jumper wires Putting more than one wire into a Nest thermostat connector can damage your system and your thermostat. Instead of using jumper wires, Nest Learning Thermostats use an internal jumper between the Rh and Rc connectors.
What color is the C wire in a thermostat?
Blue wires are also called “C” wires because they are the Common 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.
Where does the red and white wire go on a thermostat?
Most two-wire thermostats wire have a red and white wire encased in a brown insulated coating. Strip the red and white wires back about 1/4 inch at both the thermostat and the furnace ends. Connect the white wire to the “W” terminal on the furnace and thermostat.
Where do the wires go on a Honeywell thermostat?
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. Some thermostats have a jumper switch, some have a metal staple, others may have a plug, and the jumper may also just be a wire connecting the two terminals.
Should my thermostat be on E or F?
The thermostat fan operation switch, labeled FUEL SWITCH in the diagram below, is factory-set in the “F” position. This is the correct setting for most systems. The “E” setting will allow the fan to turn on immediately with the heating or cooling in a system where the G terminal is connected.
Is the common wire black or red?
Black wire: This is a hot wire that carries electricity from the power source to the first switch in a typical 3-way setup. It’s also called the “common wire” or the “line wire.” Unless the breaker is off, this black wire is always hot.
What happens if you connect a black wire to a white wire?
It will produce a big spark and hopefully blow a fuse or trip a breaker. If you wire them together and then turn the power on, the spark will occur at the breaker or fuse. Either way, don’t do it.
Which color wires go together?
The neutral is white, the hot (live or active) single phase wires are black , and red in the case of a second active. Three-phase lines are red, black, and blue.US AC power circuit wiring color codes. Function Line, 3-phase label L2 Color, common red Color, alternative orange.
