2600W+ unknown heat

I’m at a loss and don’t know what to check. I have a 2600 unknown heat that I originally thought was my dryer. I turned on the dryer and it turned on.

However, now I see it come on (between 2600 and 2800 watts - kicks on at 2800 and then drops to 2600 for about 18 minutes) and I can’t find it or figure it out.

I’ve checked the furnace, range/oven, jacuzzi (including turning off the breaker), and the dryer. When it kicks on and off I don’t hear anything at all change in the house. The water heater is gas.

What else should I be checking, any ideas?

Would you happen to ha e a heat pump with auxiliary furnace heat?

I don’t believe so… we just moved into the house in June. A heat pump was not something that we were told about during purchase and I don’t notice any devices out of the ordinary - what would I be looking for?

It looks just like an outside unit for any air conditioner. It’s actually almost exactly the the same thing. No way you could tell by just looking at it but it would have a model number to look up that would tell you.
An easy way to see if it is, the next time your heat comes on, go outside and see if it’s running. If it is then you have a heat pump. Now it might not run every time the heat comes on according to settings. If it’s cold enough to below 40 degrees then a lot of installers set this temperature so the furnace will burn instead. But if it’s 50 degrees or more outside and your heat turns on, that’s what I would check.
Also if you could take a screenshot of the signature of the waveform of a single cycle it would help identify as heat and motors and compressor s look very different. I can’t make out what the individual cycles are in you screenshot
But does appear like a compressor from what I can see
By the way, welcome!

There is an AC unit outside, but not a second device - or would it look the same? I’ll go out and check the next time I see that the unknown device is on. That said, it was about 30 degrees the last time it turned on.

Any other things I should check in the meantime? Do compressor units show as “heat”?

Can I see/screenshot a waveform when the device isn’t on?

I suppose I should add - the most recent time this device was on, the heat was not running.

Your outside untibthat your thinking is just an A/C unit could very well be a heat pump without your knowledge. There wouldn’t be anything additional on the outside that would give it away as there is just a couple small parts inside the cabinet that make the difference.
Sense usually gets devices right in classification but not always. I’ve had sense detect a motor that was actually a heater and a heating device it thought was a motor, it just happens. That’s where we come in and help “train” sense by tracking down what it is and then properly naming and classifying the device.
Now when you get a detection and sense calls it something and it’s wrong, you can leave it be and sense could learn what it is. I haven’t had much luck with that. But if you don’t give it a name and leave the sense name or if you do t turn the slider “This i is a guess” to off, then sense might rename it on you or worse yet, combine it with another device and it be wrong. I always go and rename every detection until I know what it is for sure. I don’t get fancy. If Sense names it “heat”, I name it heat ???, just something to remind me I don’t know what it is and to keep Sense from doing something with it.

You might get some insight (in general) by looking at the different legs of your panel feed. If the 2kW+ is coming from a multi-phase circuit then you’ll see it in Settings>Home>Sense Monitor>Mains when it’s actually running. You’ll have to look at it live. The load split is lost in the aggregated waveform that is just showing the total current x volts from both legs. Sometimes uneven load splits can be revealing. It’s unlikely, for example, that anything over 1,800W is on a single phase unless you have 20A or larger wiring/devices. Chances are you won’t learn much because the load will be evenly split but you never know.

I’m confused about what makes you think it’s not the dryer? My dryer looked similar first, and was the same wattage. I thought it was maybe 1 heating core out of two that sense detected (I don’t even know if that makes sense or not).

I then noticed that Sense was conflating my dryer and another device. I submitted a support ticket through the app and the team quickly pushed out a change that cleared up the conflation and found the full 5000 watts I was expecting for my dryer.

If you turn the dryer on and off, while watching the graph, does Sense show the device turning on and off too? I guess in the case of the dryer, it may not be quite that simple because Sense (for mine at least) detects the heating component, but not the motor, etc. If you catch the Sense device on, is the dryer running, and does it stop when you open the door?

Because it fires when the dryer isn’t running. All day long for 10-15 minutes.

Does it correlate to when the dryer is actually running? The rest could be device conflation.

It has to be a 240 device because even with a 20amp breaker (maximum for 120volt) the device would draw only 2400 watts. And I seriously doubt you have anything 120. And 20 amps in your home, it would be rare unless it’s a top end power tool. You’d be throwing a breaker if it weren’t the only thing on the circuit.
This should be easy to identify by going and turning off double pole breakers and then flipping one on at a time. Flip only one at a time on and see if it comes up. If it runs every 15 minutes then you won’t have to wait long.

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So right now the dryer is off, the furnace is set to two degrees under the current temperature and isn’t running, the dishwasher isn’t running, the house is silent, but this unknown heat is at 5800 watts.

Looks like possibly a 5500 watt water heater

Water heater is gas.

It’s definitely coming from one of your 240 breakers or you have a situation like another member had where they had two 120 breakers wired as a 240. The latter is not according to NEC and a hazard.
If you have gas then you probably have few 240 breakers so might be easy to find.

Do you have electric floor heating? Maybe in a bathroom?

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At that wastage his bathroom would have to be huge. Electric floor heating is usually 9, 12 or 15 watts a square foot.

Nope. This is driving me crazy.

How many 220v (e.g. dual) breakers do you have? And, this (25 amps @220v) would require at least a 30 amp breaker. Looking at your panel should provide potential culprits.

One thought I had was multiple 110v circuits accidentally conjoined…which does happen (rarely). But this is too much power for that.

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