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My thermostat has only two cables. Am I appropriate for ecobee?

ecobee thermostats require a C (popular) wire to energy on. If the current thermoregulator utilizes just two cables (R and W, or T and T), you can find an installation that is few available, dependent on the job.

Before starting, please note the annotated following:

    You’ll not manage bestbrides org to install the Power Extender Kit (PEK) with heat-only 2-wire systems. The PEK can only just be properly used on furnace or temperature pump systems which do not have C cable — it is because the PEK calls for R (energy), G (fan), and Y (compressor) cables to use, and these 2-wire systems that are heat-only not need these G and Y cables

To ascertain compatibility, you shall need to access both the wiring at your thermoregulator along with the wiring at your home heating in which the thermoregulator wiring concludes.

If you’re unpleasant doing this, you can touch base to ecobee help for guidance, or employ a specialist to help in installation

  • Based on what amount of free cables you’ve got behind the wall surface in the thermostat, some of those choices will require extra elements that aren’t added to the ecobee, including operating brand brand new cables and/or purchasing an external 24VAC transformer, SP/NO isolation relay, or Fast-Stat Common Maker

    For those who have one thermostat managing your heating system, continue to step two below.

    Action 2:Determine how many additional cables you have actually behind your wall surface during the thermoregulator

    Eliminate your thermoregulator from the wall surface to check out any unused cables which can be maybe not presently linked to your thermoregulator. Make sure to check always behind the wall surface during the thermoregulator aswell. In many cases, the cable bundle during the thermoregulator will contain much more than two cables total, with many unused cables readily available for usage.

    Note this true quantity down and continue to step three.

    Action 3:Determine just what wiring terminals you’ve got on your own home heating

    The next thing involves confirming exactly what your thermostat cables connect with at your heating gear.

    Make a note of the wiring colours at your thermoregulator together with kinds of terminals they have been linked to. Next, find your thermoregulator wires at your heating gear. You’ll want to find the true part of which the two low-voltage thermostat wires join up together with your gear.

    According to the make and model of one’s gear, your thermoregulator wires may hook up to the immediate following:

    • Wiring terminals such as for instance R, W, and C at your furnace
    • A fuel valve with terminals such as for example Th, Tr, and Th-Tr
    • T/T connections, frequently attached to an Aquastat


    In case your thermostat cables connect with terminals marked R and W, installation can be straightforward as linking a 3rd cable to your typical regarding the furnace or boiler’s low-voltage point that is common. According to your furnace, this can be either a terminal marked “C” or “Com 24V”, or perhaps you might have to find where in fact the popular may be linked to.

    Every furnace and boiler who has a 24vac transformer will have a standard terminal—just trace the 2 low-voltage wires to check out where they connect with. If you have a preexisting connection point, then touch the C cable from the thermoregulator only at that point. Often cutting/stripping the wire that is common splicing the thermostat’s C cable are often needed.


    Merely link the free cable to your connection point that is common.


    If you fail to have any extra cables, you’ve got two choices:

    • Run a extra cable at your thermoregulator down to your gear
    • Buy and install a Fast-Stat Common Maker


    A different is always to power the ecobee having an outside 24VAC plug-in transformer. This transformer could be attached to a wall surface, and could be wired as follows:

    • The 24VAC transformer cables would hook up to RC and C regarding the ecobee
    • The 2 cables in your old thermostat would connect with RH and W1 from the ecobee

    NOTE: Ensure the transformer is with the capacity of 24V AC production ( perhaps perhaps not DC output)

    January 19, 2021

    My thermostat has only two cables. Am I appropriate for ecobee?

    My thermostat has only two cables. Am I appropriate for ecobee? ecobee thermostats require a C (popular) wire to energy on. If the current thermoregulator utilizes […]