The common wire, usually labeled C, should go in the C Terminal of the Zen Thermostat. A wire labeled O, B, or O/B is used to control whether a heat pump is in heating or cooling mode. However, on some thermostats, a wire labeled B is the common wire C. In most cases, the common wire is labeled C.
What is b wire on thermostat?
O, B, O/B: These wires are responsible for switching the changeover valve in a heat pump system. The O wire reverses the valve from heating to cooling, and the B wire switches the valve from cooling to heating.
What is b/c wire?
C wires or varying colors apply to every thermostat, but blue C wires belong to thermostats attached to a heat pump. Blue wires are for heat pumps. This wire connects to terminal B on your thermostat.
What is the B terminal on furnace?
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 color is b wire on thermostat?
Blue
Thermostat Wiring Color Code Chart
| Marking | Wire Color Code | Description |
|---|---|---|
| Y2 | Yellow | Secondary cool call relay |
| G | Green | Fan relay |
| O | Orange | Change-over relay to cool relay |
| B | Blue | Change-over relay to heat relay |
What does the C-wire do 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.
What color is C-wire on thermostat?
blue wire
The blue wire on the thermostat is the Common or C wire.
What is B on heat pump?
The O/B terminal is for heat pump systems and is used for the reversing valve.If the “B” option/position is selected the reversing valve defaults to the cooling mode. It is extremely import that the correct mode is selected. If you get it reversed the heat pump will cool in the heat mode, and heat in the cool mode.
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.
Does Trane have C wire?
The blue wire is the C wire. Using a multimeter set to AC volts, you should measure about 24 volts between the red and blue wires. Connect a wire between the blue wire terminal on the transformer, and the C terminal on the thermostat. That should get you up and running.
Does red wire go to RC or RH?
There is no standard for the colour of the RH wire, but most units use a red one. The RC wire, on the other hand, refers to red cooling. It’s the same with the RH wire in that it powers the thermostat. For the RC, it powers the cooling system.
How do you identify C wire?
It is easy to see if you already have a c-wire connected to your system. Simply remove your current thermostat face from its baseplate and look for the terminal labeled with the letter c. If this terminal has a wire attached to it, you have an active c-wire.
What color is W2 wire?
| Traditional Thermostat Wire Color Codes | ||
|---|---|---|
| Color | Terminal | Use |
| Light Blue 2 | Y2 | Switched to Cooling |
| White | W | Switched to Heating |
| Brown 3 | W2 | Switched to Heating |
What does W1 and W2 mean on a thermostat?
In a conventional system, W/W1 controls your heating system and, where applicable, W2 controls your heating system’s second stage, which helps warm the home faster.In conventional cooling systems, Y/Y1 controls the first stage of cooling and Y2 controls the second stage, which helps cool down the home faster.
Is the C wire hot?
Typically, the wires that provide the power (often called the hot wires) are labeled Rc (cooling) and Rh (heating).
Is the C wire blue?
The blue wire, or C-wire, is known as the common wire. It’s there to provide power to the thermostat.Power comes into the thermostat on a wire connected to the transformer, which is usually red, and returns to the transformer on the C-wire, which is usually blue, but it can be black.
Can the C WIRE be black?
The C wire’s color isn’t standardized, so its color can’t be guaranteed across all HVAC systems. It is most often either blue or black, unless the installer did their own rewiring to create a C wire.
Is the C wire Green?
Blue or Black C Common wire, may be unused by your existing thermostat. Enables continuous power flow from the Red wire.Red Rc 24VAC (dedicated to cooling call) Green G Fan.
Is the C wire Brown?
If your thermostat doesn’t have a separate connector labeled C and you’re not sure what type of system you have: A brown wire is mostly likely a heat pump wire and should be connected to the O/B connector on the Nest thermostat. If the B wire is blue, it should most likely be connected to the C connector.
Is heat pump O or B?
The O and B terminals are for heat pumps; the B terminal is used in conjunction with Rheem, Ruud, or any other manufacturer that energizes the reversing valve in the heat pump’s heating mode. Most other manufacturers of heat pumps will utilize the reversing valve for cooling including the O thermostat.
Does Goodman heat pump use O or B?
A Goodman reversing valve is usually powered during cooling using the thermostat’s “O” terminal output. If the thermostat is set to “Cool” mode, you can check to see if it is putting out 24V on O.
Contents