Labels, Colors, and Other Qualities That Will Help You Understand Your Thermostat
Your thermostat is the control center for your home’s heating and cooling needs. This little device on your wall gives you important information about your system’s health and allows you to control the temperature.
Many of today’s models include options for scheduling your heating and cooling needs, including smart thermostats that connect to your home Wi-Fi, can be controlled by your phone, and can even learn how to keep your home more comfortable over time.
Understanding the ins and outs of your thermostat, including the wiring, can help you keep your home comfortable and efficient, and can help you understand your options when it comes time to upgrade your thermostat during HVAC service.
The Basics of Thermostat Wiring
Installing, upgrading, and troubleshooting a thermostat requires basic wiring knowledge. As expert HVAC service technicians in Kansas City, our team knows exactly how to approach any variety of thermostat.
First thing’s first: Thermostats don’t come with wiring. The wires used to hook your thermostat up are in your wall, not the thermostat itself. These wires run from your HVAC system to the appropriate terminals in your thermostat and enable the device to communicate with your HVAC and vice versa.
Important note: Always refer to the manufacturer’s product guide for your specific thermostat and HVAC system before making any changes. If you don’t have the hardcopy version that came with the unit, most manufacturers house PDF versions online.
How Thermostat Wire Terminals Are Labeled
Thermostat bases may feature up to 16 labeled wire terminals, depending upon the device’s functionality and the HVAC system it’s designed to control. Not every terminal will necessarily have a wire passed through it.
Many thermostats control hybrid split systems, which is the most common type of HVAC we service. These systems are characterized by separate indoor and outdoor units, with one run by electricity and one powered by gas. You may see a grid of wire terminals labeled something like this:
| RC | |
| RH | |
| O/B | |
| Y | |
| G | L |
| W/E | Y2 |
| C | W2 |
So what do those letters mean and how do they relate to the wiring?
RC and RH stand for “red cooling” and “red heating.” If you have a split system, it has at least two red wires in your wall and it does matter which one goes where when hooking up a new thermostat.
The O/B terminal connects your heat pump. Heat pumps are becoming more popular around Kansas City as their designs improve in efficiency, but for many area homeowners, this terminal won’t have a wire going to it.
The Y terminal is for a yellow wire that connects to your air conditioning compressor. The G terminal is for a green wire that connects to your system’s fan and controls its speed. The W/E terminal is for a white wire that connects to your heating.
The C terminal is for your control wire, which could be blue, black, brown, or purple. This provides the thermostat with continual power, essential for smart thermostats and programmable thermostats.
Are Wiring Colors For Thermostats Universal?
Unfortunately, thermostat wiring and color categories aren’t standardized. The main reason why is because there are a variety of HVAC systems and thermostats with different functionality.
Red, yellow, white, and green wires should always be the same across the board; red for power, yellow for cooling, white for heating, and green for the fan. Beyond that, there are fewer universal color-codes for thermostat wiring.
If you’re seeing a lot of other wire colors, or just aren’t sure of what should go where even with the labeled terminals, don’t panic! Just call an expert for HVAC services!
Should I Remove My Thermostat Faceplate Before HVAC Service?
No, it isn’t necessary for you to remove your thermostat faceplate before having us come out for HVAC service. It’s a good idea to leave the thermostat as-is, so we can assess any issues that might be stemming from the thermostat itself before we start checking the wiring or set you up with a new thermostat.
When we install a new thermostat for you, we’ll inspect the wiring and terminals first to identify any potential issues. Some thermostats may require additional wiring or wiring adaptors before they can safely connect to your HVAC.
Contact us today for a quote on a future-forward, energy-efficient thermostat upgrade that delivers customized comfort.