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#1

I just installed sense, in our 1700sqft home. Nothing fancy in the house, just normal appliances, 1 split/ductless AC and one forced air system.

While watching the power usage this evening, sense is showing that something is using a ton of electricity (like 5kw) every 30 seconds. Cycling on and off.

So, I turned off every light in the house, shut off the A/C’s and it still didn’t go away. So, I pulled the breakers on the 2 AC units, and still nothing. The baseline dropped - but not the surges.

Any ideas on what I am doing wrong, or if the sensors are picking up something else?


#2

@daniel,
That looks something real to me… Looks like 5kW or so. Do you have a big pump for well, septic system, sump that is cycling more frequently than it should ??


#3

My hot water heater looks like that when active - 5kW bursts on the heating elements.


#4

Thank you both, I found that it is the dryer. I feel pretty stupid.

I guess my wife was doing laundry, and I didn’t notice.

The good news is, that I now know my Samsung dryer uses 5kW, and runs on a 30Amp breaker.

Time to switch to Natural Gas dryers.


#5

Even without a single identified device, Sense makes most people much more aware of what’s happening in their house :wink:

ps: If I could find zero-carbon natural gas I would consider it. But today I can only get 100% renewable electricity.


#7

which one of the samsung dryers do you have? I just bought a new set… I switched from nat gas to electric because the samsung are very efficient… yes, they use a lot and the numbers are big during the actual cycle, but over a year of normal use, they are some of the most efficient on the market…

washer: Samsung WF45N5300AV/US : 80kWh/yr est @ 5 loads/wk (approx 0.308 kWh/cycle)
dryer: Samsung DVE45N5300V/A3 : 644kWh/yr est @ 5 loads/wk (approx 2.4 kWh/cycle)

these are a breath of fresh air compared to my old Whirlpool top loader washer and dryer set…

washer: Kenmore Series 70 110.26752502 : sense monitor approx 300 kWh/yr
dryer: Kenmore Series 80 110.76862500 : sense monitor approx 350 kWh/yr + natural gas

for me, the slight additional electricity used from my solar budget was within my est production and got my home a step closer to net zero… I know I can’t get to net zero completely, but I’m going to be real close… anyway, my dryer looks as your does on the sense monitor… the electric heater in my dryer is 5300 watts… so it looks bad at the time, but remember that even though it may look bad, its the total at the end that counts… if its anything like the ones I just bought, its efficient…

if you want to compare the electric vs gas of the same model… the gas version of my dryer would be about 0.2~0.3 kWh for dryer + the natural gas use… here in CA, they don’t rate the gas efficiency of dryers (I don’t know why not, they do for everything else), but my 15+yr old Kenmore set, family handed down 2x, was nearly 3/4 of my gas bill… the only other gas appliances I have is a 82% AFUE tankless water heater and 81% AFUE furnace… my stove and all else is electric… if anyone has an electric stove, the power use on Sense looks just like the above graph of an electric dryer…

even now, in the dead of winter, my furnace is only running for about <3hr/day and as a family of 5, we limit showers to <15mins each… with the exception of the occasional BBQ, my gas use should be very low from now on… my est is <$10/mo average…


#8

Thank you for those numbers, as our 2nd dryer died a month ago and we’re looking to replace it – and I have been debating between gas and electric.

In Utah, our Natural Gas is really cheap, but we’re rural so our electricity is very expensive. Our local electric company also found a loophole, and does not have to buyback solar or discount our service for it.

I have definitely loved the efficiency of these Samsung front loads. As you mentioned they are much, much better than the top loads or my old LGs.

With a family of 6 (4 little kids) Sense is showing our Dryer is running at 1,834kWh per Year. (4,580w while on).

Your numbers, even across brands, shows at least a 50% cut between gas and electric. That would save us about $100/year. That’s probably worth the extra $100 in the dryer. Not worth changing while a dryer is still good, but certainly worth changing to gas when one dies.


#9

Speaking of dryers, I recently bought a new dryer and have an observation…

This is a Maytag MED5500FW dryer, and it has a “energy saver” feature that presumably lowers the cycle temperature and extends the cycle time. I would imagine that this does indeed reduce the direct energy consumption from the dryer, but I’m wondering what the energy penalty of the increased cycle time (with its associated increase in exhaust and outside makeup air) is via the HVAC system? At some point I will use Sense to compare a normal cycle with an energy saver cycle to see the difference in direct energy consumption. Then I can calculate how many cubic feet of air are exhausted during the increased cycle time to see how much conditioning that air costs at different times of the year. My hunch is that it only makes sense to use energy saver cycle in shoulder seasons, when outside makeup air doesn’t need a lot of heating, dehumidification, etc.