EcobeeInstalling your ecobee with a boiler and AC is compatible with the external transformer.

There is a dual transformer system if you have a boiler and an air conditioner.The installation process for a dual transformer system is not the same as a standard installation.

There are two wires from the cooling transformer to the heating transformer in a dual transformer setup.

C wire must come from the cooling side.The ecobee will not work with a thermostat that has a C wire.If you don't already have a C wire coming from your air handler, you have two options.

The C terminal on the air handler is connected to the G wire on your ecobee.This option requires the installation of a jumper wire between G and Y at the air handler control board, which will ensure that the fan will engage when air conditioning turns on.The fan will not run if the jumper wire is not installed.Since you are re-purposing your fan wire, you will lose independent fan control with this option.

If you need further assistance with your installation, reach out to our support team.To ensure prompt service, please have wiring pictures at the thermostat, boiler, and air handler control board.

The store is open Monday to Friday and Saturday and Sunday.

The store will be open on Saturday and Sunday from 9 a.m. to 9 pm.

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