The answer is yes; it was a problem. The wiring wasn’t done correctly. I had an HVAC guy come out. He suspected that whoever installed my thermostat cheated by using some lower grade wire and doubling them up.

Why does my thermostat have 2 wires?

When it comes to low voltage systems, a 2 wire thermostat is usually known as a “heat only thermostat” and is used for systems like a gas furnace (with only heating option). A 2 wire thermostat can not be used for HVAC systems with a cooling option, or heating systems with multi stages or a heat pump.

How many wires does a Honeywell thermostat have?

The most common configuration is five wires. However, you could see as few as two and many as ten. Make a note of any present wire not connected to a terminal. Do not label these wires.

What is an S1 and S2 wires on a Honeywell thermostat?

S, S1, S2: These wires run directly outside and provide outdoor temperature information to the thermostat.

What happens if you wire a 2 wire thermostat wrong?

If you get it wrong, the heat will run continuously. Once you have them paired, attach one pair to “24VAC” (R) and the other to “Heat call” (W) on the thermostat. Doesn’t matter which one, since the thermostat just shorts them either way.

What color wire goes where on a Honeywell thermostat?

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).

Is RC and C wire the same?

The C and Rc wires are not the same. To install this thermostat you should follow the exact same wiring of the previous thermostat.

Will a thermostat work if wired wrong?

The connection of the wiring from the thermostat to the indoor unit control board could be incorrect or a wrong thermostat could be have been installed for the system. It only takes one wire that is incorrectly installed to not allow the system to work properly.

How do you wire a Honeywell thermostat?

Quote from Youtube video: Just look around the thermostat or just try prying on it gently from all sides until it comes off this one comes off pretty easy. Like that and you can see all the wires.

What happens if you install 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.

Should RC and RH be connected?

If you have both an Rh (Red-heat for powering the heating) and an Rc (Red-cool for powering the cooling), then the R wire can be connected to either Rh or Rc. If you only have a single R wire, then it will only have an R connector, which is the connection you’ll use.

Where does the red wire go on a Honeywell thermostat?

The Rh wire connects to your heating system as opposed to your cooling system. This wire may be red without an “H” attached to it, depending on if you have a dual transformer setup. The Rh wire connects to the RH terminal on your thermostat.

How do you wire a 2 wire thermostat?

Quote from the video:
Quote from Youtube video: I have the two wires coming through black and white you're gonna need to know which is which which is constant hot and which gets power when the thermostat kicks on.

How do you wire a 2 wire Honeywell thermostat?

Unscrew the two wires from the terminals. Remove the motherboard of the old 2 wire thermostat and put the new 2 wire thermostat in its place. Reconnect the red and white wire, tighten down the set screw, and put the control panel back on. Test the 2 wire thermostat wiring by turning the furnace on.

How many thermostat wires do I need?

Most systems today require a minimum of 5 wires when both heating and air conditioning equipment is included in the system. Our pro recommendation is to use 18/8 wire.

Where does the W2 wire go on a Honeywell thermostat?

This wire should go directly to the heating source whether it be a gas or oil furnace, electric furnace, or boiler. White for W Terminal. W2 – This is the thermostat terminal used for second stage heat.

Should I use W1 or W2?

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. If you have a heat pump system with auxiliary heating, you’ll normally connect the AUX/AUX1 or W2 wire to the ecobee’s W1 terminal.

What color is W2 wire?

General Thermostat Wiring Color Code

Terminal Wire Color
W2 Brown
G Green
C Blue/Black
O/B Orange/Dark Blue