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

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

ecobee thermostats require a C (popular) wire to energy on. When your current thermoregulator utilizes just two cables (R and W, or T and T), you will find a few installation choices available, based on the application.

Before starting out, take note the annotated following:

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

To find out compatibility, you shall want to access both the wiring at your thermoregulator along with the wiring at your heating system where in fact the thermoregulator wiring finishes.

You can reach out to ecobee support for guidance, or hire a technician to aid in installation if you are not comfortable doing so

  • According to what amount of free wires you have got behind the wall surface in the thermoregulator, many of these choices will need extra elements that aren’t incorporated with the ecobee, including operating brand new wires and/or buying an external transformer that is 24VAC 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 wires you have actually behind your wall surface in the thermoregulator

    Eliminate your thermoregulator from the wall surface to check out any unused cables which can be perhaps perhaps maybe not presently linked to your thermoregulator. Make sure to check always behind the wall surface in the thermoregulator aswell. The wire bundle at the thermostat will contain more than two wires total, with numerous unused wires available for use in some cases.

    Note this true quantity down and proceed to step three.

    Action 3:Determine just just 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 equipment.

    Make a note of the wiring tints at your thermoregulator additionally the kinds of terminals these are typically attached to. Next, find your thermoregulator wires at your heating equipment. You will need to find the point in that the two low-voltage thermostat wires join up together with your equipment.

    With respect to the make and model of one’s equipment, your thermoregulator wires may connect with the annotated following:

    • Wiring terminals such as for example 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 linked to an Aquastat


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

    Every furnace and boiler which has had a 24vac transformer will have a standard terminal—just trace the 2 low-voltage wires to see where they connect with. Then tap the C wire coming from the thermostat at this point if there is an existing connection point. Often cutting/stripping the wire that is common splicing the thermoregulator’s C cable are often needed.

    IF AN EXTRA is had by you CABLE

    Merely link the free cable to your typical connection point.

    IF NO EXTRA is had by you WIRES

    You have two options if you do not have any additional wires:

    • Run a wire that is additional your thermoregulator down to your equipment
    • Purchase and use a Fast-Stat Common Maker


    Another solution would be to power the ecobee having a external 24VAC plug-in transformer. This transformer may be attached to a wall surface, and could be wired the following:

    • The transformer that is 24VAC would connect with RC and C from the ecobee
    • The 2 cables on your own old thermostat would connect with RH and W1 regarding the ecobee

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

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