Water Heater thermostat setting (Now: how water heaters work and half detecting 220V devices)

Ah, ok. I see. But the Usage screen or the Water Heater device under the Devices tab isn’t showing the full 4500W, right? That doesn’t sound like a UI or timeline problem, if so, but rather just that Sense hasn’t correctly IDd both legs of the water heater.

It has to be software otherwise the timeline and the device screens would reflect the same information. It appears the device screen is correct and it’s just the timeline and the tags there that are off. It has to be picking up both legs for the full 4500 to be calculated anywhere. I had originally though it was a problem with one leg but that does t explains 120 devices with the identicalreporting of half the wattage.

I might be misunderstanding then. Can you post a screenshot of the usage stats for the device? The images you posted show the 2600W being detected as water heater and I’m guessing the other 3000W are relegated to Always On, other devices, and Other.

Please look again at the screenshots as it shows everything you need to see clearly. Look at where the timeline gray bar is and how the total reflects about 4600 watts when the only change is the reported 2300 water heater. Yes, always on is also included in that total it’s the 999 after

I have learned that you should take the little flags (Water Heater -2313W) on the waveforms with a grain of salt for two reasons:

  1. They don’t show up for every change in the timeline. Not sure exactly when they show and don’t, but you shouldn’t count on an exact match between the tags and the timeline alerts.
  2. The values that show up on the tag are closer to peak values, rather RMS values that are diplayed by the waveform trace. You will see tag values that represent extremely short-term (how short Sense hasn’t said) overshoot and undershoot. So don’t do localized arithmetic using those values.
    @RyanAtSense, I think you have a thread somewhere telling us more about those tag values ?
    @samwooly1, sounds like you understand wave theory, so you know the difference between peak and RMS ?

When I was having this issue Sense was detecting the whole ~4500W, but only tagging half of it to the water heater device (~2250W)…the other half was showing up in “Other” for me. That appears to be what your screenshots are showing…the total drop between the two is 5635-999=4636W, but only half-ish (2312W) getting tagged to the Water Heater. My guess is that your “Other” category dropped by ~2250W between those to screenshots as well.

Of course, that doesn’t explain what you’ve been seeing with 120V devices, but the water heater usage looks exactly like what mine looked like when I was having the issue.

For me, it self-resolved over time…Sense eventually identified the second leg as a separate “HEAT 2” and I was able to merge that in so it shows the whole ~4500 tagged to the water heater.

It would still be helpful if you could share this information. In any case, this largely sounds like an issue Support should deal with as they can actually look at your data, including what’s happening behind the scenes.

ETA: My suspicions line up with @timwagner80 in that only half of your water heater is getting detected here. The total will decrease by the entire amount regardless of what has been detected as that number (and the power meter) are being drawn from mains data and not your detected devices. Nothing seems incorrect UI-wise here, but that’s really a call for Support to make as they can dig much deeper into your data .

Yeah, sure do understand. On mine it’s undervalued consistently. It started with the water heater being off by half on the tags but the total was correct so I assumed it was reading one leg. But then I have a device not yet detected that I can see cycle on the timeline that shows half the wattage also. It will show 240-270 watts but I know positively that it is 540. This device is 120 volts so my theory of reading one leg was wrong.
I have also seen where the tags are not always showing on the timeline. That doesn’t necessarily bother me except I’m not sure if that throws the device page calculations off.
While there is a lot of useful information here in the community I would appreciate answers from tech support concerning the questions and concerns I have that either haven’t been asked or addressed here.
I’m last the pint where I regret buying it at this point. There description and tech specs were too vague for my liking but as-is there is still plenty to be happy about.

I’ve contacted through report a problem many, many times. They don’t respond except for the automated email stating a promise to get back to me. Still waiting on the phone call I was scheduled for the day before yesterday, changed to yesterday and changed to today. It’s after five now so they’ve missed three appointments that they have made with me.
What information do you want me to share exactly? I’m more than happy to supply you with whatever information available to me.


A whole thread on those tags - not sure we know exactly what they represent yet, but you shouldn’t use them for any of your calculations.

I’m not going to publicly comment on the status of your support tickets. We have a small support team and they cannot respond immediately to support requests.

This thread is veering far into issues where the community can longer help. You need to wait to hear from support on this. They are the only ones with access to your high-resolution data and who can accurately assess what is happening here. No one here, myself included, can solve this.

And yes, as @kevin1 notes, there are some ongoing issues with tags as have been pointed to in other threads. They are not perfect representations.

What’s so strange about minenis the other half aren’t showing in other or another device and it appears that the calculations on the device page are correct. I’m hoping it will resolve itself.

Sam how long have you had sense? These things can take time.

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I think for the amount of time I’ve had it that I’m extremely fortunate. I just went and looked, it was January 15th so 9 days, even shorter than I thought.
Here are a couple screenshots of what I have now. A few I’m in the process of accurate identification as sense was wrong with what they were or just have them generic heat names
Something I feel may help with device detection is not changing anything right away. As my wife would see the graph she would turn something off to save money. I had her stop that and just act like life before sense. We are doing things just as we always have. Whether this truly helps, I don’t know. But from what I’ve read from others their detection hasn’t been as good as mine. I had three events today. A new detection and two where sense changed the names based on what it though previously detected mystery devices actually were.
Fridge, coffee maker, oven, heat pump and water heater are all correctly identified. I have a heat I believe is for the dryer as it’s come on twice for a high heat cycle and we usually use extra low heat. I’ll merge if it keeps happening

The 16 devioderected has now dropped to 11

You are absolutely fortunate. That’s great for only 9 days! My detection period had a similar speed, but I live in a small-ish apartment, so it wasn’t that shocking.

This thread is moving away from water heater content. If you’d like to continue documenting your detection experience (and I encourage you to do that…there’s some great similar threads on here), you should create some sort of “Wooly’s Detection Journal” in Share Your Sense Stories.

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Did you see where I lost 5? I’m not sure when this happened but tech support has me uninstall the app, restart the phone and reinstall. Could have happened when I did that or before. Others have had the disappearing act and posted about it. It was a first for me and a lot to lose at one time.

Well, even 11 is pretty good for 9 days. Support can help figure out what went wrong there.

In the meantime, let’s just keep this thread focused on water heater detection.

I’m surprised that people have trouble with water heater detection, it was the first for me. It’s been spot on regarding the timeline and notifications. Some of the others might get missed here and there but not the water heater.
Can tech support force a detection? I would imagine so. Electric water heaters operate at only three wattages, 3800, 4500 and 5500. Now my timeline might show 4500 or a lot of the time half of that but the tag is alwys there and the device page will display either the correct 4500 or 2700 but the totals on all pages reflect the correct wattage.
I was just giving that information to help anybody that may have their water heater currently detected as a mystery or something else.

I was mistaken Ryan. I counted some twice. It was not ever 16 just 11