Sense hasn’t detected my fan yet, or at least reliably separated it out. It has been showing me a “furnace” that runs for 10 minutes and uses 481w, but it turns on at seemingly random points. Maybe that’s my central fan? Anyways, I can say that my AC uses 4,000 watts when on. Is yours 120 or 220? 900w seems like a very small AC, or mine is very large.
Not sure how small your AC unit is but my recently detected 3 ton AC unit runs about 2300W and the undetected furnace fan runs about 625W for comparison. Of course the AC unit will vary by weather conditions. On the power graph I’ve manually measured it a few hundred Watts higher on an exceptionally hot day.
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Well, this is very much not the direction I hoped this discovery would take.
My AC is a sizable unit. I looked at the tags, and the compressor has an amp rating (RLA) of 19.9 and the fan an amperage (FLA) listed at 1.4. This implies that I should be seeing ~5,100W draw.
Now for the philosophical question. Since this still effectively cools the house at 20% of the electricity usage, should I actually get it fixed? The air intake sits right at the top of the basement stairs, so I suspect that the AC is actually just pulling in cool basement air and recirculating it.
How are you determining that your AC only pulls roughly 700 watts as you stated it’s not detected?
I suspect it’s pulling the wattage it’s rated at or there is no way your unit would be working effectively at that low wattage.
Likewise, my Air Handler (and fan) via CT on my 5 Ton System is pulling only about 425 watts.
I’m watching the power meter as the AC kicks on. I can see the jump when it does, but it’s only jumping by that amount. It’s also fairly common for my total house usage to only be about ~1,500W when the AC is running and none of the other major appliances are on at the same time.
I’ve been investigating this further, and I’ll start a new topic for this specific issue once I put together some numbers I just got my electricity bill, and I’m seeing a big gap in my total electricity bill and what Sense is reporting. The numbers for everything else in my Sense usage looks reasonable, but the AC wattage looks incredibly low, and my power bill is higher by an amount that suggests the AC is being reported to my utility, but not being reported to Sense.
Just a thought but assuming it’s a 240V AC system you could watch the individual mains values in the Sense Monitor when it comes on and see that both go up by the same amount. Maybe one of the current clamps isn’t quite right and it would show up there. I guess you could also plug a known load like a lamp into an outlet on each power leg and see if they measure the same on the power meter.
August has always been a peak bill for me in Florida.
5 Ton single speed installed in 2018. House about 2800 sqft.
Just received my August bill through the 18th. It’s down about ~30% this year from last year.(Avg Daily 112 down to 82).
Total according to bill was 2,390kWh vs Sense at 2,488.3kWh. Bill was actually only 29 days this time compared to Sense calculating at 30 days.
With adjustments, Sense and bill appear to be within about 10kWh of each other for the period. Considering I do not know time of day Smart Meter is read, that seems pretty close.
Only installed Sense in late June so I cannot compare individual items to last year.
2 things since last year.
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Smart Meter installed. I guess this could play a part
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Installed an additional return vent in my den that is 13 ft high at its peak. Additional return vent is about 6 inches from ceiling where hot air should be. Other return vent is at floor level and snakes up internally in wall to the attic.
Ceiling fan in center of room always on.
The room felt very hot last year and an additional floor fan was used to move more air around. It’s felt much cooler this year without the floor fan (which measures at 170 watts). Though that’s only about 4kw a day/120 kw for the month (or $50 for the month). An additional Enviracaire Air Filtering unit has been installed which negates around 120 watts of the 170 watts.
Using Ecobee Thermostat data, it appears my AC ran about 453 hours a year ago vs 293 this year in July both years as August not available yet (And notice this is also about ~30% less).
I also set Ecobee to make sure AirHandler Fan runs a minimum of 15 minutes an hour per forum suggestion. That’s new for August.
We’ve had near record setting heat days this month. But also what I thought was 2 weeks of a lot of rain and overcast, though it’s always over 80 in Florida this time of year.
I can only point to the added return vent as the most likely factor - really getting the hot air off the high ceiling and out of the house
Picked up the vent at Home Depot and about 30 ft of flexible line. So it wasn’t very expensive either.
To be clear, a few digital clock (radios mostly) came out mid 70’s. Remember hand held calculators that only did add, subtract, multiply and divide as function if Space Program first came out early 70’s ($299 for Pioneer believe it or not). TI came in with more complicated calculators in mid 70’s.
At that point only 3 kinds of digital clocks.
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Panasonic had a unit with flip cards on wheel that slowly rotated with metal piece holding card up. When it moved far enough it flipped to next card. ($59 iirc)
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Sony had a round wheel for hour/min ten/minutes one. Numeric printed with a paint/ink that glowed under black light. They slowly rotated around ($69 iirc)
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GE actually click radio with true electronic numerals. Nixie tube type. ($99 iirc)
More and more digital penetration in early 80’s as VHS recorders became the norm, but they really did not replace analog in mass until mid to late 80s.