supportedThermostatModes isn't supposed to be JSON_OBJECT?

[bravenel]

The corrected code looks like this:

setSupportedThermostatModes(JsonOutput.toJson(["auto", "cool", "emergency heat", "heat", "off"]))

def setSupportedThermostatModes(modes) {
    sendEvent(name: "supportedThermostatModes", value: modes)
}