The E terminal has a back-up heat source. If you have a heat pump package unit, the E terminal should be wired directly to the heating relay or the stripboard of the air handler.
What is the e wire on a Honeywell thermostat?
The E wire controls emergency heating. Emergency heat is used when the HVAC system is not functioning properly (usually when the compressor is out of service). When you set a thermostat to emergency heat, the system bypasses the compressor and directly accesses the electric heat strip.
What color is E wire on thermostat?
Brown
Thermostat Wiring Color Code Chart
| Marking | Wire Color Code | Description |
|---|---|---|
| E | Brown | Emergency heat relay |
| Y | Yellow | Primary cool call relay |
| Y2 | Yellow | Secondary cool call relay |
| G | Green | Fan relay |
What is W2 and E on a thermostat?
That is why, on many old thermostats, you would jumper Y1 and W1 in a heat pump application. W2 Means second-stage heat.E Is emergency heat, usually just a way to manually drive on what would normally be the secondary form of heat without stage 1 heating.
Where does the e wire go on a nest?
1 Answer. The ‘E’ typically goes to what is called ’emergency heat’ which is often the same as and is connected with the ‘AUX’ (auxiliary heat) used with a heat pump system.
What is the E and F switch on Honeywell thermostat?
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 E terminal on a thermostat?
E – This thermostat terminal is for heat pumps and stands for Emergency Heating. If for whatever reason the heat pump condenser fails and it is necessary to run the heat there is an option on heat pump thermostats for emergency heating.
Where does Brown wire go on Honeywell thermostat?
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.
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 are the 5 thermostat wires?
5 Wire Thermostat Wiring (Any HVAC Device Air Conditioners, Heat Pumps, Furnaces, etc.)
- Red wire for power (24V).
- White wire for heating (connected to W or W1 terminal).
- Green wire for fans.
- Blue or yellow wire for cooling (connected to Y).
- Black wire for C or Common wire.
Where does orange wire go on thermostat?
The orange wire connects to terminal O on your thermostat. The orange wire only applies to homeowners with an air-source heat pump. Only air-source heat pumps connect to your outdoor condenser. Homeowners with geothermal heat pumps have no use for the orange wire.
Where do thermostat wires go?
In general, the thermostat wire colors match the first letter of terminal names such as Red Wires for R terminals (for Power), Yellow Wires for the Y terminal (for Cooling), White for the W terminal (for Heating), Green Wires for the G terminal (for the Fan).
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.
How do I know if my central heat is gas or electric?
There’s usually a small window located on the front of the heater. Look in the window. If you see a blue flame, it’s a gas heat exchanger. Other units will have a small metal panel that’s easy to remove.
What are the switches on the back of the thermostat?
In non-digital thermostats there are two switches. These switches move small metal balls that make contact between different traces on the circuit card inside the thermostat. One of the switches controls the mode (heat or cool), while the other switch controls the circulation fan.
Where does the brown wire go?
Brown is your hot wire so you want to connect that to your building’s black wire. The blue is negative or return, so that will go to white. Green with yellow stripe is the ground and will go to the building green.
What is black wire on thermostat?
Blue or Black C Common wire, may be unused by your existing thermostat. Enables continuous power flow from the Red wire. Red R 24VAC power from the furnace’s transformer. Red Rc 24VAC (dedicated to heat call)
How do you connect 4 wires to 2 wires?
How to Connect a 4 Wire Line to 2 Wires
- Take the ends of both the 12-2 ROMEX® wire and the 12-3 ROMEX® wire and strip 1/2 inch of insulation off each wire. Push both ends into an electrical junction box.
- Look at the four wires of the 12-3 cable.
- Alternatively, use the red wire as the hot wire.
What is the common wire for on a thermostat?
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.
How many wires does my thermostat have?
Most systems today require a minimum of 5 wires when both heating and air conditioning equipment is included in the system.
What is a common wire?
The common wire is normally the white wire, at least in the United States, and is often called the neutral wire. It’s also called common because all circuits in the house typically have the white wires tied together, which means every circuit has that wire in common.
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