Smart HVAC Systems

I described a role for a home energy monitor such as Sense in this description of future Smart HVAC Systems.

See: The Idea Incubator/Smart HVAC Systems - Wikiversity

Does anyone know if such systems are currently available or under development?


There’s many integrations that can accomplish these tasks already. Since the HVAC unit simply receives commands from the t-stat, the smartness comes from the t-stat and associated smart devices within the residence. Here’s a few examples of how this can be done

  • Indoor AQI can be determined with devices like Awair and integrated with Nest or Ecobee stats directly or through HA integrations and automation
  • Outdoor AQI can easily be observed through HA without the need of devices (using APIs) and it can control any number of mechanisms based on automation.
  • Indoor humidity can be determined by t-stat add-ons and devices like Awair and perform tasks based on humidity through native t-stat integrations and HA
  • Sense data could be used to control devices through HA. For example if current load is over 10k and indoor humidity is above 80% wait for load to be 5k before turning on the AC to reduce humidity. If over 90% disregard electrical consumption.
  • Carbon monoxide, carbon dioxide, or volatile organic compound readings can easily be determined by devices like Awair and natively activate HVAC systems or through the use of automation like those with HA.

Have you are anyone else tried the offering in addition to Sense for more AC info?

No and honestly I (personally) wouldn’t spend money on that. Here’s why:

  • Filter alerts: this is provided by both ecobee and nest
  • Daily Insights: this is provided by both ecobee and nest
  • Tech Messaging: Just call the tech … They just want you to use their techs which is how they make money
  • System status: this is provided by both ecobee and nest
  • Freeze alerts: this can be done via any number of home automation platforms and even through free phone apps.
  • Water leak alerts: they just use a sensor like any other that can be purchased online, zigbee, zwave, wifi etc. I have many water sensors throughout my house using zigbee and HA.
  • Breakdown risk score: This is just a guess.

Unfortunately, there’s nothing in your HVAC unit that’s smart. It’s fairly dumb for the most part so this app doesn’t do much more than make assumptions based on what it knows is going on and to an extent nest and ecobee do that as well.

Guess I was more interested in AQI.

I’ve tested a number of AQI devices. Personally, I would recommend Awair:

It also integrates into Nest, IFTTT and Ecobee natively without the need for any third party.


@lee , some day I would like to add outside intakes and automated dampers that let me blow outside air into the house when the outside temp is in the Ecobee set zone (maybe a little tighter band). I would probably try to do it using Home Assistant with Node Red since I’m already using Home Assistant with Sense, NuVent, and Ecobee integrations.


I don’t include AQI, but I have created some performance monitoring for my 2 HVAC systems. My main goal was to track when heating or cooling show degradation vs past performance, but looking at temperatures in the registers closest to my two air handlers.

More on what I can see here, but the main thing is that I can see how far those registers drop when the cooling comes on, and how warm they go when the furnace is on. Plus the electrical energy expended.

For anyone looking to monitor PM2.5 on the cheap, check out this project that inserts an ESP8266 into an IKEA $12 air quality sensor: