Hello sgonsalves,
As you may know, HRV/ERV control are very limited at the ecobee thermostat, and even more limited in the APIs, as I’ve discovered recently, see below thread:
http://developer.ecobee.com/api/topics/not-able-to-control-the-ventilator-from-the-apis
Ecobee just told me that the next October’s API release will enable more HRV/ERV control, see below thread:
http://developer.ecobee.com/api/topics/ventilatorminontime_is_it_used
In the meantime, you can use the MonitorAndSetEcobeeHumidity smartapp and enable ‘Free Cooling’ by setting it to true. However, you’d need to hook up your HRV as a dehumidifier (in your ecobee thermostat’s installation settings), and not as a HRV (b/c APIs don’t allow any control).
P.S. You’d need to grab the ecobee device and MonitorandSetEcobeeHumidity latest code at https://github.com/yracine/device-type.myecobee as I’ve made many changes recently to avoid
creating hold events by using new setThermostatSettings functions.
Regards/