AC detection

It is variable speed could I turn it up high enough to shut off then turn down several times a day to get it to detect it

You really can’t force a detection like that. I’ve tried the many cycles on my own, even hundreds without it helping.
If you have a way to control your fan speed then setting it to always run at single speed may help it to detect but it would only be detected for that speed.
I personally don’t think your HVAC system will ever be detected but hopefully I’m wrong.

Thanks Sam, that stinks I know my unit is to be one of the best for energy but I believe it is my main issue. We was promised a 40-50 percent reduction on our power bill and it only dropped about $10 monthly.

Those units are extremely efficient even when running constantly. The main thing is, they work in combination with a well insulated home. You’d be surprised by the effect of having air seepage somewhere or insulation not being what it should be somewhere.
I was in construction for 20 years and have seen insulation installed incorrectly in about 95% of them. Foam is where I’ve seen people really getting taken for a ride.
I don’t know about your electric utility, but mine does a free “energy audit”. They come in and test the home with thermal imaging and a blower door test to find leaking areas. Sure helped me fix areas that I did t even know were an issue.

@MaheshAtSense and others have recently answered some AC detection questions you might find helpful:

The blog link there is also very detailed

I’m going to add one more thought to the mix here. Sense mostly relies on spotting characteristic (basic physics) responses to devices turning on and off - that is devices where the intrinsic physics of the underlying device is directly exposed to the house grid when the device is switched on (and off). Many electronic devices from that contain variable/DC motors or AC->DC power supplies, hide their physics behind active electronics (things with transistors, feedback, etc.) which makes them much harder to identify.


I have a Trane system just like what you describe. Variable speed compressor coupled with a variable speed air handler. It’s not really that it’s designed to never turn off (when I look in the Nexia app at the history, mine is usually running about 19 - 20 hours of the day) but it’s designed to run at a low speed, most of the time when the amount of temperature drop is low or it wants to maintain a temp. This also helps keep humidity from getting to high.

I know others are saying that Sense will either never, or have a very hard time detecting your system. This could be true; every house is different. I’m a new Sense user (less than a week) but I’m optimistic Sense will be able to eventually detect when my AC turns on. Because of the variable nature of the compressor, it slowly ramps up it’s speed. This is what mine looks like when it turns on, runs for a minute at a high speed, and then slowly ramps back down to a medium speed. It makes a very clear stair-step pattern.

Also, Sense has already detected what I believe to be my variable speed air handler. Granted, it seems to not be 100% accurate. I suspect it’s only picking up certain speeds, but I know it’s the air handler because I flipped the circuit breaker to it off and it immediately switched to off in Sense.

Wish you the best of luck. My experience is that Sense does best with fairly sharp start up and stop, not slow ramps, and that’s one reason that it struggles with modern devices that do things more gradually. However, as noted, Sense behavior is very different from situation to situation, and they are improving over time, so who knows.

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I’m with @andy and wish you luck but completely agree about startup and shutdown signatures.
You mate get a speed detection but it’s likely to report incorrectly when transitioning from one speed to another instead of turning on and off.

I do know Sense has made progress with this type of ramping up, it’s how EV’s charge.
They have made a lot of headway with EV’s due to the popularity here.
How many users have the same type of variable system like yours, I don’t know.

I would also add that over time the detection aspects will improve while the dataset is the dataset (to a greater extent, but not exactly).

For those familiar with non-destructive image/video editing, you can “modify” an image by creating interative instructions to apply changes to the image without altering the underlying image. e.g. LightRoom vs Photoshop. You aren’t screwing up your data in a potential one-way path to the wrong image if you use non-destructive methods.

From what I understand there are certain necessary data compressions that Sense carries out so there is a kind of selective “destructive editing” going on. That said, the parsing of the stored dataset can be completely revised over time … and this in turn can modify the way Sense “sees” and post-compresses incoming signal at the monitor itself. For example, at the monitor it seems clear that Sense really needs to be looking at the highest resolution during larger variations (“storing the interesting bits at higher resolution”) in load but once something is detected as “on”, Sense processing can focus attention elsewhere assuming that the device has some kind of predictable load. What can happen by parsing the historical dataset is that over time that device’s load can be estimated more precisely. The ramps in DC loads, for example, can be separated out in the dataset because of known other devices being subtracted from the signal.

What that means is that sometime in the future we may well get a complete rebuild of the historical dataset interpretation that both revises past, present and future device detection.

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I have the same question.

Sense has been installed 4-5 days now. Here in the south its HOT so AC has been running alot but not constantly (off during the day when i’m at work).

Curious why it hasn’t detected it yet.

From another thread it appears the variable speed blower/air handler has been detected (only when it goes into “high speed” mode. I would assume my AC is variable speed too (same mfgr).


I also ha e a Trane air handler but it’s not variable. Same manufacturer doesn’t really mean much, it’s the type and design of the system.
At 4-5 days, your still very new and it’s possible to have it detected that quickly but unlikely.
I think it took about a month for mine the first time I installed and over a week after I reset for detection.
When it is detected, you will probably have one leg (120 of 240) detected first. So it will show half of the actual consumption while the other half will end up in “other”. Sense will get them both at some point.
I would give it a month at least.
I have 2 garage doors used every day that haven’t been detected since January

Cool, thanks Sam

I have a Trane system and Sense worked great on detecting it for the first year, now it is a crap shoot, somedays it does, somedays it doesn’t. No changes to the system just can’t rely on sense anymore being correct, it even worked on picking up the auxiliary heat on it during the winter.

Looking at my usage graphs it has big spaces where it just looses seeing it for an entire day then pick it back up at night.

So while you will be happy it “senses” it, I hope it is able to keep “sensing” it.

I have a Trane/American Standard heat pump with 15kw heat strips. Sense detected and accurately reported usage on the compressor as one detection and then the heat strips were actually 2 separate 7.5 kw detections.
That was first time around. Installed January and then started over with reset about a week ago.

Haven’t used the strips since reset but heat pump compressor was detected early, just a couple days

I have a Trane XL20l two stage compressor which Sense found within a week of installation. It’s also very consistent in detecting the on and off of each stage. It still hasn’t found my air handler and doubt it ever will.

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My compressor runs on the 2nd stage most of the time anywhere from 45-75percent for about 19 hrs straight I’m in florida. We had all the insulation done in the attic 3 mths ago and didn’t help. Mine also is XL20i

I’m in Florida as well. Here is today. Stage 1 runs followed by stage 2.

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What about your nexia

I use a Ecobee 3 now, Nest before that.

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