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How To Wire A Honeywell Thermostat With 7 Wires

What are the 7 thermostat wires?

Thermostat Wiring Color Codes. Thermostat Black Or Blue Wire (“C” Wire) Thermostat Red Wire (“R” or “Rc” Wire) Thermostat White Wire (“W1” or “W2” Wire) Thermostat Green Wire (“G” Wire) Yellow Thermostat Wire (“Y1” And “Y2” Wire) Other Wires (BK, RS1, RS2, ODT1, ODT2, AUX NO, AUX C, AUX NC).

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.

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.

What color wire goes where on a thermostat?

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 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 if there is no C wire for thermostat?

If your current thermostat didn’t need a C-wire, it (or a wire that can be used as a C-wire) might be rolled up inside the wall. This wiring indicates a line voltage system, and you’ll need an adapter or a smart thermostat designed for line voltage.

What is the B terminal on a Honeywell thermostat?

W/B: The W/B terminal controls the heat relay or valve. When the thermostat calls for heat, a signal is sent to power up the furnace and the blower fan or the boiler, heating your home.

What does L1 and T1 mean on a thermostat?

The brand and type of thermostat would help to be certain. The L1 and L2 are probably the power connections; Line 1 and Line 2. T1 and T2 are probably the thermostat switch terminals. For heat, T1 and T2 contacts would “close” when the temperature is falling and it reaches the set point.

Why is there a jumper between R and RC?

Effectively there isn’t a second RH wire, although there is an RH terminal. However, the heating still needs to be controlled, so a wire known as a jumper is connected between the RC and the RH terminals so that power gets to the heating control part of the thermostat.

What are the four wires in a thermostat?

In general, the heating wire (often white), goes into the “W” port, the cooling wire (often yellow), goes into the “Y” port, the wire that sends power from the HVAC system to the thermostat (often red), goes into the “R” port, the fan wire (often green), goes into the “G” port, and the common wire (often blue), which.

What is the common wire on a thermostat?

WHAT IS A C-WIRE? A C-wire, or a common wire, runs from your low voltage heating system (24v) and carries continuous power to your thermostat. In today’s electric market, most newer heating and cooling systems have C-wires, which guarantees compatibility for the installation of all smart thermostats.

Does R go to RC or RH?

Here are some general guidelines: An R wire can go into a Nest Learning Thermostat’s Rc or Rh connector. The Nest Thermostat E only has an R connector, which is typically where an R wire would go. These are not jumper wires, and you can insert the Rc wire into the Rc connector and the Rh wire into the Rh connector.

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.

What is the blue wire on 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.

What is white wire on thermostat?

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.

Can I use the G wire for the C wire?

If there is no hidden C-wire, you can use a G-wire instead. However, you will not be able to use your fan independently when the heating or cooling isn’t running. Also, many HVAC systems are incompatible with this solution, including: HVAC systems using electric heat.

Can I use Nest thermostat without C wire?

Nest claims that you can use the Nest Thermostat without a C-wire. While this is true, it would be advisable to have a C-wire. A lot of Nest users have had problems when they use the thermostat without a C-wire. In the absence of a C wire, your thermostat battery charges itself by using the power from your HVAC system.