Thermostats

Understanding Ecobee Smart Features Vs HomeKit Smart Features and How They Interact

Ecobee:
Ecobee has a number of "smart" features designed to automatically save money on heating and cooling. Some examples include:

• Ecobee knows the outside temperature via a connection to the Internet

• You can add additional SmartSensors in other rooms of the home that measure the temperature of that room

• SmartSensors also know if the area is occupied

• You can setup "Comfort Settings", for example: Away, Home, Sleep. These Comfort Settings can be scheduled to enable at different times each day of the week. So for example, you can set the "Away" temperature as a baseline, then set a "Home" temperature for when a room is occupied, and then set a temperature for sleep, based on a time of day. These three simple settings and their schedules can handle 95% of what people want to automate with regards to temperature control.

• You can control and access the thermostat from your mobile device or a web browser, even when you are away from home.

• The Ecobee system also learns how quickly it takes to heat your home, and how the outside temperature affects the temperature in your home, as well as the patterns of when you are home and away, and can use this information to adjust how it responds to these factors.

HomeKit:
So the Ecobee Smart Thermostat already has most of the automation and "smarts" built into it that you would need to build and manage in HomeKit. But you could also choose to manage your thermostat using HomeKit sensors and scenes and automations. I feel that the interface and features for managing your thermostats is somewhat easier in the Ecobee system, because it is designed specifically for these features. Also HomeKit doesn't really have a nice way to organize and manage long lists of automations. I think if I could name HomeKit automations and group related automatons into folders, then I might do more thermostat management with HomeKit. That being said, it would be very straightforward to create a couple of simple automations in HomeKit that would control your temperature based on HomeKit motion and temperature sensors in your home, as well as integration with HomeKit Scenes.

Interactions:
When you add your Ecobee system to HomeKit it is important to understand how the two smart systems interact. The key part to understanding this interaction is understanding what the thermostat does when you adjust its temperature manually. Normally the thermostat's temperature will be determined by the current Ecobee Comfort Settings you configured when you setup your Ecobee system. If you manually override the current temperature —for example by walking up to the thermostat and adjusting the temperature, or by manually changing the thermostat's temperature in the Ecobee app— the thermostat's temperature will adjust to that temperature and go into "Hold" mode, and the Ecobee Comfort Settings are temporarily ignored. You can control how long your thermostat stays in "Hold" mode in the Ecobee software. There are five options available:

• 2 hours

• 4 hours

• Until the next scheduled activity

• Until I change it

• Decide at time of change

Any changes made by HomeKit are considered a manual change (like using the app or the thermostat itself to temporarily adjust the current temperature) and will place the Thermostat in Hold mode. So this means that after you use HomeKit to change the Ecobee's temperature, what the thermostat does next is based on the setting you have for Hold Mode. It will either go back to its normal operation after 2 or 4 hours, at the next Ecobee scheduled activity, or stay at that temperature until you manually change the temperature again. This allows you to use HomeKit to control your thermostats in a couple of different ways.

Keep in mind that there is no setting in either Ecobee or HomeKit that lets you always determine which system is controlling the thermostats (short of removing Ecobee from HomeKit). Making a change from either HomeKit or Ecobee will always override the thermostat's current temperature until the period of time determined by Ecobee's Hold setting. The scenarios below merely outline how you could use the two systems together. Here are a some scenarios:

• Ecobee Primarily Controls Thermostats: If you never use HomeKit to adjust temperatures, you can still use the Ecobee's sensor information to drive other HomeKit automations, or just to conveniently view the Ecobee temperature and sensor information in the Home app.

• HomeKit Primarily Controls Thermostats: If you set Ecobee's Hold Mode to "Until I change it", then any thermostat change you make in HomeKit will drive your Ecobee thermostats temperature settings. You can use the Home app to manually change thermostat temperatures or build HomeKit scenes and automations based on variables in your home, and HomeKit will essentially drive the control of your thermostats.

• Hybrid Control: If you set Ecobee's Hold Mode to a time-based duration or the next scheduled activity, then you can use a combination of Ecobee and HomeKit rules and automations to control your thermostats. The thermostats will be driven both by your Ecobee Comfort Settings and Activity Schedules and HomeKit, based on which ever system sent the last change and the Hold duration. Depending on how complex all of your Ecobee and HomeKit automations are, this might get confusing as to what current settings are in effect, but it can still be effective. For example you could set a baseline configuration using Ecobee's Comfort Settings and Activity Schedules and then use HomeKit to override the "defaults". Maybe you keep the basement cooler in the winter because you don't use it often, but your home theater is in the basement. You could put a temperature change in your "Watch Movie" scene to adjust the basement to be warmer. Or maybe in Ecobee you set a liberal "Sleep" schedule starting at 1:00 AM so the house stays warm longer for when you stay up late, but you often go to bed at 10:00 PM. You add a lower the heat setting to your "Go To Bed" HomeKit Scene that causes the Ecobee to turn off the heat earlier. Another option would be to use daily HomeKit scenes to set the temperature for when you get up, go to work, come home, and go to sleep that change the thermostats temperature 95% of the time, manually triggered exactly when you want them to (rather than relying on Ecobee's sensors and schedules), but you don't have to worry about forgetting to trigger the HomeKit scenes every single night, because the base Ecobee Comfort Settings and Schedule will also go into effect as a "backup/default".