Multiple Air Handlers w/ Dedicated Circuit Monitoring

I have 2 identical AC’s & 2 identical Air Handlers (AH).

When an AC turns on so does its AH. When the Boiler turns on so does its AH.

I have 2 Flexible Sensors, one on each AH 240 Watt Dedicated Circuit.

On 11/12/20 @ 6:50PM I started the AC & AH for my downstairs and verified both were on. Sense initially recognized this as my AC for upstairs at 1531 Watts. Sense did not recognize its corresponding AH. However, the history disappeared shortly thereafter.

On 11/12/20 @ 7:18 PM I started the AC & AH for my upstairs. Sense detected both as AC Upstairs at 1509 Watts and AH Upstairs 525 Watts.

On 11/12/20 at 7:28PM I again started my AC & AH downstairs, and there was no recognition of this showing up by Sense as AC Upstairs or AH Upstairs. Sense has never recognized the AC or AH Downstairs despite having a Flexible Sensor on the AH.

Obviously, I am confused. However, Sense also seems confused? Any suggestions or observations will be greatly appreciated. SteveH

Can you clarify what devices Sense has detected natively before you started with the Dedicated monitoring of the two different air handlers.

What are you expectations that should be happening? When all is working correctly, Sense will be able to accurately identify the AH Upstairs and AH Downstairs.
I would not assume that this will let it differentiate the AC Upstairs or AC downstairs as those circuits are still only being detected by the main CT’s.

Sense natively identified my AC Upstairs before I added the Flexible Sensors. Then after the Flexible Sensors were installed Sense identified my AH upstairs. Sense has not as yet identified my AC or AH downstairs. Thanks for taking the time to ask this question.

Shouldn’t I at least be receiving usage data on my Flexible Sensor for my downstairs AH even if Sense doesn’t natively recognize it?

I forget to indicate my expectations. I would expect that when AC turns on the associated AH will also turn on. My hope would be that Sense is able to identify them both whether or not it is upstairs or downstairs. If they are only recognized as a single event each then I would expect the wattage to indicate a total for both, i.e. 1500 Watts + 525 Watts or approx 2025 Watts. I am getting the feeling that my expectation is unrealistically optimistic.

Hmm. The Downstairs AH should be detected with the flex sensor. It makes me think something didn’t go right during setup as with the Dedicated Circuit setup., Sense no longer has to “detect” anything. With the DCM, you are effectively saying “any current through this clamp = device which I call AirHandler (Downstairs), so don’t bother trying to figure it out”.
So if you are turning on your downstairs air handler, and the device you created in the DCM setup isn’t turning on, something is amiss.

Since Sense had already detected AH Upstairs, you should merge the Sense Native detection with the DCM device to make sure its not still trying to find AH Upstairs separately.

As for the two AC units - I don’t believe there is anything in the sense system that “attaches” a device to another device. Yes, our human logic is "IF AH Upstairs turns on, AND we see additional spike that always happens at the same time (or a constant interval after AH), THEN must be related to AH Upstairs.
Or even if some form of that logic exits, if the AC units look the same to Sense, it doesn’t matter which air handler turns on because the AC units still look the same.

This doesn’t solve your problem, but if you are interested in a bit more about AC detection with Sense, they have two different blog posts that shed some light on it.

which also talks about trying to differentiate between identical units
and links to this post
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I have read the 2 blog posts and your suggestions a number of times and thanks for the information. There is a lot to unpack here.

We seem to be in agreement that the Flexible Sensor (DCM) installation was not successful, so why not uninstall it and let Sense verify natively what it sees, hopefully the AH upstairs. The AC upstairs was previously natively identified. If this happens I may want to reconfigure what I want to use the Flexible Sensors (DCM) for. Also, we are at the end of the AC season anyway.

I have tried to search for how to uninstall the Flexible Sensors, but to no avail. Not sure what this entails or any ramifications.

I think reconfigure is easy. Move the Flex CTs to your new targets and then rerun the setup via the Connected Devices > Sensor Monitors menu. If you don’t want to keep the history, delete the two previous devices.

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I recently reinstalled my 2 Flexible Sensors on my 2 Air Handlers as the original setup was incorrect. After about a week 1 AH has been recognized, but the 2nd AH signature has not yet been recognized by Sense and no wattage usage has been identified. Both AH’s are identical.

Did you make it through setup on both AHs the second time, especially the sequence where you turn each device individually from off to on manually ? I ask that because I actually put my second CT on the wrong 240V hot line and ended up monitoring my floor heat instead of my second EV charger. But I discovered that issue in the off-on stage of setup.

One other thought - DCMs just measure, so if you truly are getting 0W of usage all the time (share a screenshot of the Power Meter in the phone app for that device) , you could have an open CT or a pin/port problem on you second port. Best to contact

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Hi Kevin

Yes, I did get thru the whole sequence the second time around as you indicated in your email.

If I understand correctly, any screen shot of the AH Power Meter that has not been identified will show no activity whatsoever, so I am not sure why I would need to make that screen shot unless it is to prove my statement. Is that the case and if so I understand the need to verify from new users?

Thanks for your continuing interest in my issue.

If you hooked the CT to your air handler and made it through the, it no longer requires detection - the power data comes straight out of the CT and voltage measurements. No detection required. Your the AH Power Meter should be showing exactly what the Flex CT and voltage measurements are seeing.

Should be enabled if you made it through DCM (Direct Circuit Metering) setup

You should have real usage statistics based on Flex Sensor DCM measurements

And real waveforms bases on measured data from the Flex Sensor on your AH

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Hi Kevin - Yes, my Settings > My Home > Connected Devices > Dedicated Circuit Monitoring all as you indicate above. However, no data whatsoever for one of the Dedicated Sensors in my Attic. Please see note below that I just sent to Sense a few minutes ago. Interesting that the attached Condensate Pump is recording properly, the only other device on the circuit. It does beg the question if I have my FS on the right breaker. Will keep you posted to their reply. Again, thanks for following up. Steve Hoff

“I installed my 2 Flexible Sensors about 10 days ago on my 2 identical 240 Watt breakers for my 2 identical Air Handlers, each with a duplex plug for its own Condensate Pump. The AH in my basement is working fine and indicating when my AH and CP are on and using wattage. The AH in my attic does not show any wattage use whatsoever, but the attached CP on the same breaker is showing wattage use when activated. Is this normal or is their a problem? It doesn’t seem right to me. Thanks, Stephen Hoff”

Thanks for sharing. What I’m hearing is that you are seeing the condensate pump (CP) usage on the circuit using the DCM Flex Sensor (CT), but not the air handler (AH) that you think is on the same circuit ? If so, I don’t see any way that they both could be on the same circuit, because the Flex Sensor and DCM just measure the usage, with no detection needed, once set up.

One more question - are you sure your air handlers are really 240V ? I ask because I have a similar setup - 2 furnaces, one in the garage and one in the attic, and the AHs on both are only 120V. If that’s the case, you might have a 240V circuit, but with the AH might be fed off the opposite leg from the CP in the attic.

ps: I was wondering how you managed to make it through DCM setup without the AH being spotted, because the setup needs to see something turning on, but it must have seen the CP turn on.

I have been thinking about this since I sent you the email earlier. The CP was detected early in the process and is its own device. That is why the wattage shows up. I double checked that I had the right circuit attached to the FS and it is. Both AH’s are on 240 Breakers. I have the FS on the black wire for both circuits, not sure if one should be on the white wire, but I am under the impression from reading that it doesn’t matter. I don’t think that while going thru the DCM process that the CP triggered acceptance. I distinctly remember turning on the AH before completing the process. Puzzling.

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Hi Kevin - Here are some screenshots that I finally figured out how to make. Not sure if they will help but these are what my Sense shows. Steve

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Hi @cpari101.

Did you wind up reaching out to about this issue? If not, I’d recommend reaching out so we can take a look at what we’re seeing on our end. It might also be helpful to gather some photos of the configuration of the sensors inside your panel if you have not already, just so support can get an idea on how they’re currently set-up.


I suggest the same as @JustinAtSense. Support should be able to diagnose. From the screenshots you posted, it looks the AH up isn’t seeing enough current through the CT to show as on or standby (even when my car isn’t hooked to the charger, my Tesla DCM will show a couple watts usage, but show as off).

Yes, I did contact Sense support and Tyler just responded. He asked for pictures and pointed out that my 2 AH’s do not appear to be the same as I was informed when I built our house. Here is my reply to him with the pictures I sent.

Hi Tyler - When I had this house built I was told the 2 AH’s were the same. It now sounds like they are not and the one in the Attic is very hard to get to for me since it is very tight quarters. My Bad! They are both on 240 Volt circuits (See Below) The one on the upper right is the AH Attic which is not being recognized. The one on the lower left is the AH Down which is being recognized.

The AH Down on my device shows activity on 10/21 @in 10:30AM, 10/24 @ 2:00AM & 4:15AM, 10/25 @3:30AM. Perhaps this will help you identify which is which from your data. There is no activity on my AH Attic


Thanks for sharing… Sounds like you have some interesting discoveries ahead. One more question - you talk about your air handlers as if they are separate units. What kind of heating / cooling do you have to go with each ? Furnace, AC compressors, or heat pump ? Age and brand would also be interesting.

I’m asking because I really only know my own systems - the furnaces with integrated air handler are 120V and actually plug into a dedicated outlet, hence I can use an HS110 on them, whereas my AC compressors are 240V