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I live in a 3,500 sq. ft. house in Minneapolis, MN, my power bills have been extremely high, and I'm trying to track down any sources of phantom drain as I think the draw is inappropriate.

With most everything than can be powered down, both HVAC systems off, well pump not running, computers shut down, all lights and ceiling fans in the house off (except for the utility room lights), I'm having about a 1,000W constant draw. With a current clamp, I'm reading 2.06A on one phase and 6.36A on the other.

From what I've traced down so far out of the 1kW draw:

  • 50W: Cable Modem, 2x Routers, a few monitors on Standby
  • 40W: Outdoor bug trap
  • 10W: Security Panel
  • 100W: Utility room lights while I was measuring at the panel (motion activated)

This leaves about 800W with no obvious source of where it is going. I will be tracing down each circuit next, the highest current branches being 2x ~1.5A, 2x ~1A, 3 ~0.5A, and 2x ~0.3A.

Is this anywhere in the realm of a normal phantom draw for a house of that size?

Since I'm operating under the assumption that it is not normal, what would be good items to check if I have unplugged everything that can be unplugged and the draw still remains?

Other than TVs in standby and my two refrigerators, what would be good candidates to plug into my kill-a-watt and measure their draws?

Edit

I have measured the standby/resting stable current of everything I have plugged in to an outlet, and came to 340W.

The only remaining things plugged in are permanently wired:

  • Three light fixtures that turn on when I'm in the utility room measuring current
  • light fixtures while off
  • dishwasher while off
  • furnace/AC 1 while not running
  • furnace/AC 2 while not running

These probably have some draw while off, but let's be more than generous until I measure them and say 500W total.

This means I have a solid 500W going somewhere, in my house, completely unaccounted for. Nothing I can think of can plausibly be dissipating this much power without a trace.

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    If you can see the drain on the meter - try turning off each circuit breaker one-by-one until it stops. That narrows it down to one circuit. 1000W is high for nothing - that's, like, a small vacuum cleaner going all the time. – user253751 Sep 11 at 9:52
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    How well do you know your house? Could it have a fresh air heat exchange system that is powered? Could there be a heater for prevention of freezing pipes that is hidden away someplace? Could there be an attic or crawl-space light that is on all the time? Intercom system? Antenna amplifier? Motion sensing lights? There could be a lot of standby power, but it seems more likely that there one or more substantial loads that are hidden away somehow. – Charles Cowie Sep 11 at 15:14
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    "computers shut down" Current PCs have standby supplies that stay on when shutdown. You'll need to unplug any PCs or switch them off with a mechanical switch on the back panel. (That won't take 800 VA, of course.) – Graham Nye Sep 11 at 21:42
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    As Far as phantom drain I have never found it to be real or enough to measure.what I have found... All the chargers that are plugged in even if not powering devices create a fair load you may have the laptop turned off but feel the charger / wall wart or brick most of the time these will be warm because they use electricity that warmth is watts being consumed not phantom. I used to have a commercial coffee maker I found that that thing drew an amp almost all the time keeping the water hot, sound bars , TV sets cable or satellite boxes all add up and fairly quickly. – Ed Beal Sep 13 at 16:29
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    Ehryk was the kill-a-watt meter calibrated to prior to the measurements? what loadcell were you using? What clamp was it calibrated? There is variance of .3-5% with the smaller slugs and the larger ones are worse for for pro models. power apparent and power true next what clamp? To get accurate power measurements it truly takes meter that cost about 10x any of the kill a watt meters except the ones that have multiple slugs but those start much higher. As an electrician That has worked in many fields I can tell you many meters are considered as absolute junk until the 1k$ what model do you have – Ed Beal Sep 15 at 23:34
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Older Fridges can draw upwards of 300 W (while in defrost for example), and can average over 150W even if they are working correctly. If you've got two of them, that could be your load and could explain the variance (if one were in defrost while measuring). 1KVA "Phantom" load for a 3500 sqft house doesn't seem totally unreasonable. You've already found 500-700w of draw. Everyone's circuit breaker idea (in comments above) is good to localize which circuit the phantom drain is attached to.

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  • I measured both refrigerators when running. My main fridge in the kitchen draws 7W while running, the mini-fridge draws 60W while running. Next time I shut everything down, I'll unplug the refrigerators just to take them out of the equasion, but assuming they are both running that's only 67W. – Ehryk Sep 16 at 17:14
  • Read the answer and understand the compressor is not running on most units while in defrost mode. – Ed Beal Sep 16 at 18:08
  • @EdBeal got it. I will unplug both refrigerators next time I shut everything down, as well as turning off the breakers for the two furnaces, to remove all of them as variables. – Ehryk Sep 17 at 14:27
  • You need to verify the wattage also your main fridge 7w I don’t know any electric fridge that consumes only 7w that’s barely enough to keep electronic controls running and when the compressor starts the drain will be closer to 1000w for a short time. – Ed Beal Sep 17 at 15:36

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