How do I wire my WiFi 9000 Color Touchscreen Thermostat?

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The basic installation / quick start guide is included with your thermostat (Touch here for a digital copy).

You will need:

  • Philips Screwdriver
  • Flat-Head Screwdriver
  • Smartphone or tablet
  • Level
  • Home WiFi Password

You May Need:

  • Wire Stripper
  • Needle-nose Pliers
  • Drill and 7/32 Drill Bit

Removing your old thermostat:

Turn the power off – at your breaker box or at your HVAC system (typically controlled by a mounted light switch on the furnace / air handler)

Check that the system is off – Switch your thermostat to heating or cooling and wait 5-7 minutes. If the system does not start, power is off (If your thermostat lost power when you turned off the breaker / switch, your power is off.)

Remove your old thermostat from the wall plate – Look for screws, buttons or clasps. Unscrew the screws or depress the clasps and pull the thermostat gently away from the wall plate

Check your wires – Your thermostat cannot operate with line voltage systems. Line voltage systems have thick wires black or white wires with wire nuts. Contact Customer Support for model recommendations if you have this type of wiring. Also, this thermostat cannot operate with a “communicating” system. Communicating thermostats typically have wires labeled DATA, or 1,2,3. Contact an HVAC contractor for more information on compatible thermostats.

Take a picture of your wiring – be sure to be able to clearly see each wire and the terminal markings they connect to.

Remove any jumpers – Jumpers, or small loops of wires, connect multiple terminals together.

Label the wires with the included stickers that match the terminals they are connected to.

Do you have a wire connected to the C terminal? – A C-Wire is required to power up the thermostat

If you do not have a C or common wire, your thermostat screen will not power up. The C wire connects to the C terminal on the HVAC systems’ 24VAC transformer.

A C or common wire that does not connect directly to the C on the transformer, but instead connects to another common may experience random restarts / shutoff.

Option A - Finding the C-Wire: There might be an extra wire pushed into the wall or wrapped around the wire bundle. Gently pull the wire bundle out of the wall to check for unused wires. If you have an unused wire, connect that wire to the C terminal on your new thermostat. Connect the other end of the unused wire to the C terminal on your heating/cooling system (or the zone panel if your home uses more than one thermostat to control temperature). Be sure any other wire(s) connected to the C terminal stay securely connected when you re-tighten the terminal. Not all heating/cooling equipment use the C label for the 24 VAC common wire. If your heating/cooling equipment does not have a C terminal, check the system manual or contact the manufacturer to find out which terminal is the 24 VAC common. Complete installation by following the remaining steps in this guide.

Option B - Using the C-Wire Power Adapter: If you do not have an unused wire in the wall, see the C Wire Adapter Installation Guide included with the T9 and T5+ thermostat. For WiFi thermostats that do not include the C Wire Adapter, go to to order.

Disconnect the wires and remove the old wall plate

Bundle and insert the wires through the new back plate

Insert the screws /wall anchors

Insert the jumper loop below the R and Rc terminals if you only have one R or Rc wire. If you have separate R and Rc wires, remove the jumper loop

Connect the wires to the appropriately marked terminals on the wall plate

Attach the thermostat faceplate and turn the power back on.


Wiring Details:

The thermostat uses 1 wire to control each of your HVAC system’s primary functions, such as heating, cooling, fan, etc. See the diagram below for what each wire controls on your system:


  • Y – Compressor Stage 1 (Cooling)
  • Y2 – Compressor Stage 2 (Cooling)
  • G – Fan
  • C – Common
  • L/A – A – Input for heat pump fault
  • W -O/B – Heat Stage 1 (Heating) / Reversing valve for Heat Pump systems
  • W2 -Aux/E – Heat Stage 2 (Heating) / Backup Heat
  • R – 24vac (Heating transformer)
  • Rc – 24vac (Cooling transformer)



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