AC vs Compressor vs Air Handler

My Sense detected my “AC” first after about 48 hours.

Looking at the Bubbles and the text, along with the power meter, there is always a lingering voltage of 400 or so watts for 3-5 minutes after Sense says my AC turned off. See below. It always shows in the dreaded “Other” Bubble.

Is it reasonable to assume this is the Air Handler and Sense is only detecting my Compressor?

If so, as they most likely start at the same time, is there any reason to think that Sense will ever detect the Air Handler?



It is very normal for the fan to continue to run after the compressor has stopped. This is by design and serves many purposes but is primarily on high seer units to ensure all the heat/cool is in the house and not lingering in the duct work.

If you set ecobee to fan-on for 15 minutes per hour then your Sense should see the fan more often and might increase the chance that it’s detected. It’s also good to do this to ensure proper oxygen distribution / humidity distribution in the house. If you ever purchase a air quality monitor you’ll see how CO2 rises very quickly in occupied rooms which causes drowsiness.

Another thing you might want to look at is your usage. It seems like your AC usage is unusually high for your setpoint vs the outdoor temp. I have my cool setpoint at 68 degrees and 75 when it’s 85-115 outside and I run a lot less. There’s many factors here so it could be perfectly normal, but you might want to consider thinking about that.


Though I can see where it would show if set to turn on 15 minutes per hour, I’m not seeing a way to set it turn it on for 15 minutes an hour. :thinking:

Go to your thermostat page, then go to the settings → System → Fan → Fan Runtime

Found it. Was about to delete, lol. Thanks.

Not sure about your exact setup so my experience might be different. My air handlers are part of my furnaces and on a separate (120V) circuit from my AC compressors (240V). Sense has detected both compressors and both air handlers over time, but with caveats:

  • Even though Sense eventually detected both air handler/furnaces, I put both of them on HS110s before that happened, which is better for me for a couple reasons - 1) they show me furnace components beyond just the air handler and 2) I recently discovered that the detections were maybe 70% reliable.
  • The detections for my upstairs AC compressor have started falling off recently. I continuously compare Sense vs. Ecobee using Home Assistant.

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My air compressor AND my air handler are 240, so I am unable to put either on a KASA unit.

How did you get your 240 compressor on a KASA sensor?

I think he implied that it was just the air handler. There’s no 240 Kasa devices unless you used 1 of 2 (that I know of) z-wave monitors with HA emulation.

Actually the Kasa plugs support 240v. Someone on this forum, quite a while back, hacked 2 of them together to monitor a 240v appliance. Obviously that’s against code and not something that Sense can condone, but it’s technically possible.

EDIT: Here it is: Ok to splice in two Kasa plugs to each pole of a split AC? - #16 by kingces95


If this was my community forums I would have removed that post for potentially causing someones house to burn down. In 2/3 of the pictures it appears to be 120 as there’s only a hot, neutral and ground. However in the picture with two boxes there’s two grounds and what appear to be a hot wire-nutted together. There’s also no neutrals going to those plugs, so maybe he’s using a ground as a neutral. I would seriously advise that no one follow that post.

Additionally, there’s 14ga Romex inside of conduit, which is not code and I’m willing to bet 14ga is undersized. Now that he posted it publicly, good luck on the insurance claim :roll_eyes::face_with_monocle:

So my statement stands, there are no 240 Kasa devices, and bootlegging two 120 to achieve 240 is not a 240 Kasa device. Lastly, please don’t do what that guy did.

My air handlers/furnaces run off separate dedicated plugged in 120V circuits. I can see 4 separate components using a smart plug.

  • air handler
  • igniter
  • ignition blower
  • Always On power supplying the furnace control board and associated Ecobee thermostat.

While technically possible, this is a REALLY REALLY REALLY bad idea. When (not if) you have a problem, your insurance would be totally void.

What’s absolutely needed is a legitimate approved “wire in” sensor like a Kasa (or Sense’s own monitoring) that monitors the high power systems in most of our homes that Sense can’t detect on its own. I DO NOT understand why this hasn’t been handled by Sense, because it’s a huge need.

Using the only one extra sensor on the Sense itself IS NOT a solution…firstly it’s only one, secondly many Sense owners already have solar.

Yeah, I’m going to add a disclaimer to that comment. This is obviously a potential fire hazard and Dedicated Circuit Monitoring (which was added after the fact) is a better solution here for a variety of different reasons.

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@DevOpsTodd @andy disclaimer has been added. Thanks for bringing it to my attention.

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