# The Energy Detective / old fridge = 5 kW?



## tvhwy (Dec 20, 2008)

Hi,

I rent a cottage on large lot. The lot is shared by another tenant who lives in a backyard yurt. I am responsible for my electricity bill, but the bill is mailed to my absentee landlady. She arranged it that way, she said, because the two houses are on the same meter. She is using The Energy Detective (TED) to record my usage. I report my kWh reading and cost to her and cut a check for the right amount.

I have little reason to doubt my landlady's honesty or, to judge by all the positive reviews I found, the device's accuracy if used properly. But I am taken aback by the instantaneous readings I've witnessed since I started paying attention to it.

Although it's more common to see it fluctuating between 400 and 1200 W with the 'fridge running, it'll sometimes read at around 5200 W for minutes at a time. My average usage was recorded as 26 kWh/day for a three week period in which I was absent for two weeks, and the 'fridge was turned off for five days.

So far I have not caught TED posting that ~5 kW number when the refrigerator is idle (though I have seen it hover at around 1200 W). Could that old fridge really be surging so high? Looking at its styling, I'd say it's from the early 1960's. (Although, could it really have lasted that long without having received a new and probably more efficient motor since then?)

I'm running no more than a laptop and a light bulb at these times. Water heater sounds idle, too. Hence I wonder if TED is being used properly.

My back room has a box of four outlets fed directly from the adjacent circuit breaker. TED is plugged into one of those outlets. Should TED be accurate for me? Could it somehow be that it is monitoring at least some of my neighbor's usage too? Even if the house is on a separate circuit? (Not sure if it is.) Neighbor has appeared to be home every time I've witnessed these spikes.

I will try some more rigorous experiments if I have time. I'd still appreciate your opinions, though.


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## MgMopar (Jul 31, 2004)

A old fridge compressor can draw pretty high but not that high. Good chance if it was from the 60's it could be the original equipment in it (they were work horses even thought they didn't care about energy usage). It is probably on a standard outlet (15-20 amp at 120 volt). So the most it should be able to draw before breaking the breaker on the circuit would be about 2400 watts even with a malfunction. From what you are describing for your other usage It is probably a combination Of item on when this occurs. water heater, Any electric heat like base board heating, Furnace. And just a question are you on a well or city water. A well pump can draw large current and you may be sharing it with your fellow tennent on the property?? It may be the cause of your higher numbers at times.


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## tvhwy (Dec 20, 2008)

Thanks for the informative reply, *MgMopar*. The house has city water and no heat. The water heater was silent when I witnessed the surges, so I don't _think_ it was running. It provides instant hot water, so I guess I could expect it to run sporadically when I'm not using the utility; but I can also hear it when it runs. Otherwise, as I said, I'm only drawing about 250 watts. 

Sounds like I ought to consult the landlady at month's end to reconcile the bill.


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## hoistdoctor (Jan 25, 2008)

The fridge, even from the 60's will be rated no more than 1000 watts. I would suspect that the water heater is the big user. A standard home 40 gallon water heater can have a 4500 watt element.


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