Two AC Units

I have 2 . AC Units and right now, it does not distinguish between the two (one for upstairs and one for downstairs), both the units are the same make and model so I am sure it would be difficult to read them as two different units…any ideas?

Time may be your friend. Wait for the Sense Brain to grow and with luck they may be distinguished.

Or get a Smart Plug (assuming the units are <1800W & 120V) and put one or both on those. The advantage of a Smart plug (Wemo Insight or TP-link Kasa) is that you will definitely get the units tracked right away and so can create alerts and so on to reduce consumption.

My sense also struggles with this. We have two central AC systems (one per floor). They are the same brand but slightly different sizes. Sense has been struggling to find and distinguish the individual air handlers and condensers.

With different sizes, you have a chance. Slightly different waveforms. Same size makes it pretty much impossible.

Same problem. Two exact same units. Not really an easy solution to this.

About the only possibility is one detect for either single unit and another detect for both operating at once. Those would be distinctly different signatures

I’m having a similar problem. Two separate central air units, gas pack first floor and split heat pump second. Been using the monitor four days now and Sense has detected my dehumidifier in the basement and “AC”.

Oddly, when both AC units are off, the first one to come on gets detected as AC whether it’s the upstairs or downstairs unit. Then, while it’s running and the other one comes on, it’s gets put in the “other” bubble. Doesn’t matter which order in which they start, the first one on gets labeled “AC” and the second one is “other”. I’m hoping with time it’ll sort out.

I also have this problem. My approach is , I am interested in the amount of time each furnace/ airhandlerunit is running. The compressors run the same time as the furnace, minus a minute or two. I can (or Numbers/Excel can) calculate the amount of watts being used.
Most furnaces run on 120 volts so I use a HS110 on each one. Sense never misses the HS110, but it does miss a compressor operation or confuses it with something else.

Just my approach, thought I would pass it on.

If you have indoor units that use 120v, make sure each unit is on a separate 120v leg of service. The monitor will then have a chance of identifying the two units separately.


This seems like good advice from @pswired if you can do it.

Makes me wonder … if you have, say, identical AC units that are on the same service legs and you can perhaps set one to have a LOW fan consistently and the other a MED fan consistently or other possible distinguishing signature based on your units, whether that might help Sense separate them? Of course this might be pretty inconvenient!

Do we know technically/anecdotally whether inverter & dual-inverter based AC units (which are becoming more common) have the same sameness problem? It seems like the DC-ramping might be more “unique” for the same the model units in different locations. Unfortunately, my guess is that these units might be harder to detect, period.

That might separate the two blowers, but probably not the two compressors (by far the larger power draw). Depends on what you are trying to achieve

I would like a response from a Sense rep on this one. Looking at the circuit breaker allocation for the two AC units it would seem rather simple to solve this.
The AC compressor runs on a 2pole breaker, while the AC blower fan is a single phase installation. The single phase breakers, at least in my installation, are on separate phases. The signature should be pretty distinct as to which one is tied to which when the power jumps for the compressor, but only one phase increases for the fan. Additionally, the AC units are designed to keep the blower on for about 30 to 90 seconds after the compressor kicks off for efficiency. I am only at 48 hours in and am probably not being patient enough.

On another note, i am the kind of user that would love to do a manual entry mode. I know what all of my breakers do, i could sit there, circuit by circuit and load by load and help it characterize the signature and am willing to do this with sense to help feed the machine.

Welcome @draco_cb
If you’d like a rep to answer then your better off by sending your questions or requests to support.
Although they sometimes will answer here, it would be much more reliable to get an answer that way.
At two days in, this is very new still. Patience is the key here and it will be a bit of a roller coaster. I was fortunate and in the first few months had around 25 devices but that is rare. The first week I would t expect to see more than a couple on average. Then you might have as many as four in a day with a couple weeks before seeing another.
There is a lot on here about manual entry and we all have the same feelings. I can recognize it, why can’t Sense. There is also a lot of info on here at why that is and about machine learning in general.
It will be tough, try to be patient.
I’m six months in with 41 devices. I have 13 of those being smart plugs. I’ve only had about 4 of those in the last 2 1/2 - 3 months so most came early.
Good to have you