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Thermostat wiring can sometimes be as simple as turning off your thermostats and HVAC systems power and replacing your old thermostat wire for wire to the new one, however sometimes things can be a little more complicated. Check out our step by step setup blog and get all your questions answered below. If you have any additional questions or concerns don’t hesitate to contact us for more information 

How do I wire my new thermostat?

  1. Look for the Common Wire: The common wire or the “c-wire” delivers constant power to your thermostat.
    1. Turn your thermostat to the off position. 
    2. Wait for any cooling or heating to stop. 
    3. Turn off your furnace/AC breaker.
    4. Detach your current thermostat from the wall. 
    5. Look for a wire connected to a terminal labeled with a “C” on the thermostat. 
  2. Review all wires, review our wiring color code below for further information.
  3. Install the New Thermostat according to directions, usually hooking up wires in the same locations as your old unit.

What does each wire do?

The thermostat wiring color code includes:

  • White: Connects to your heat.
  • Yellow: Connects to your compressor.
  • Green: Connects to the fan.
  • Orange: Connects to your heat pump (if applicable).
  • Red (C): Connects to the cooling system.
  • Red (H):Connects to the heating system. 
  • Blue: Common or “C” wire.

What are the different HVAC volts systems?

There are three possible volt options: a 24-volt, 110/240-volt and millivolt thermostat. The 24-volt system however is the one found in most home HVAC systems.

Which HVAC aren’t 24-volt systems?

The following systems aren’t 24-volt systems:

  • Boilers
  • Electric furnaces
  • Baseboard electric heat
  • Solid fuel stoves 

What if I don’t have a C-wire?

Contact us today to get your new thermostat installed safety. We’ll recommend the best course to take to get the most of your new thermostat and unit.

What should I do if I need help wiring my thermostat?

Contact our HVAC professionals today for all your wiring and installation needs. We’ll make sure your HVAC system and new thermostat is working correctly and efficiently together. Partnering with a dedicated HVAC contractor such as a nearby Ruud Pro Partner will help ensure that your new thermostat will be effective in your house. Whether you need financing for your new HVAC system or help finding the right HVAC contractor, we’re here to help.

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