Can't find unknown device

I have a device that turns on every 45min for about 1 min and draws 760w. Looking at the graph it does not spike when it starts, like a motor. I thought it was the roof melt, but I unplugged that and it still happens. Thoughts?

Can you post what a daily view or several cycle view looks like? Also a single cycle to show as much detail as possible.
Another thing you can do is visit the device library and look a t waveforms of many different devices. This would take longer to do if course but if you post screenshots, I would be glad to help
Library location is device detection sub-forum
And upper right corner where it say “all”, change in dropdown to the library

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I can see where it comes on an a full lot @davidpd.
If you could use the device power meter and spread your fingers to show a single waveform or just more detail in general, it would make it easier to tell if this is a resistive, inductive or other device. I’ll show you what I’m trying to explain

I found it. InstaHot under the kitchen sink.


Glad you found it. I know someone else here with one and I think you’ll be surprised at what a little hog they are. It’s like they are almost always on trying to maintain temperature of the small tank.
But I can completely understand the convenience aspect as my whole house has almost instant hot water at every outlet. Some things are worth the added cost.

That’s precisely what it is doing. Instant Hot isn’t tankless, it’s a “mini-tank” located at the faucet. I’d looked into these and decided that I can wait a handful of seconds for hot water rather than pay for the convenience. I’ve seen various estimates of their stand-by cost, but none of them are measured…perhaps someone with a detected Instant Hot can share their numbers.

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I think the whole house solution I use is more cost effective than these instant systems. I’ve calculated my monthly cost many times and with the water we don’t waste down the drain, it’s actually cheaper. It works out to a little more than one KWH a day.
I think @kevin1posted his use for this in the community library
If not, @davidpd please post yours there. That’s a really good device to have in the library.

Whole house circulators are a great solution, and I remain tempted. I certainly don’t need a bunch of tiny hot water tanks spread around the house. I’m told whole house systems use tiny amounts of power and, with well insulated piping, the thermal loss is minimal. Do you have numbers for your system you can share?

I’m not sure how much benefit there will be for us, because our domestic hot water is mainly a side effect of our geothermal (waste heat from the compressor heats the domestic hot water, even making the geothermal more efficient in the process) and we designed the house with fairly short runs of well insulated hot water piping, all within the envelope. Our longest run (to the kitchen) takes 17 seconds to deliver hot water to the sink after sitting for hours. That’s still 17 seconds of water down the drain (running our deep well pump) for every hot water use, so maybe I should invest. Seeking your advice.

When my system is turned off the water heater averages .2 KWH an hour to maintain 135 degrees. This is when nobody is using water and the pump and valves are closed for circulation.
When the system is set to on and valves opened, it uses .3 KWH for same timeframe. So it’s an added 1/10 KWH per hour and with my timers AND thermostat controller enabled for 6:30 am to 10:00 pm that’s roughly 1 1/2 KWH a day, 45 a month at $.085=$4.00. The pump is 62 watts and only runs for 5 minutes or so once to twice an hour. We have dropped water use by 1,000 gallons a month at $6.75/1000 so you see it’s almost an even trade.
My loop is 110 feet long, 55 feet to furthest shower and I’m insulated with 7.1 R-value insulation, the best you can get for 3/4” pipe.
I did a heat loss calculation on all this while designing and my heat loss should be 750-800 btu’s and hour. I do r know why but I’m actually doing better than what I had expected.
The setup I have for the pump goes like this. Pump timer can come on for hours above. But I have the thermostat controller plugged into the times socket. When water in the lines drops by 10 Degrees, the pump runs and then shuts off when desired temperature is reached. That’s why such short run times.
This system can also be used without a loop and probably what you would want for a retrofit. It’s a “Taco HLS-2 HOT LINK system”. When using their valve at the furthest faucet, there is no need for the water to recirculate back to the heater. It actually uses your cold line. If you look it up you’ll see how it works. I didn’t do it this way because I didn’t want warm water when turning on the cold faucet. It only does that a few seconds but I was being extremely picky about how I wanted everything to work.
Now the “on demand” systems are probably a little more efficient but install can cost an arm and a leg.
When I did mine I was already replacing the water heater. I removed and reinstalled all hot ware pipes and everything for this system cost me $1300 doing the work myself.

Huge thanks for the detailed response. This gives me everything I need to make a decision for our home.

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If you want to know about on demand systems, lookup or message @steve