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Back in December/January, we got a real shocker; a $400+ electric bill. I thought there must be a billing error, so I went out to the meter, and found that not only was the number probably right, we'd used another 1000kW/h since the reading (which was about a week and a half prior). This is for a modest 1600 sqft 1.5-story house; WAY outta line. My next thought was a leech; someone hooking to our service unbeknownst to us. We turned off all the lights, computers, etc etc, leaving the service panel on, and... wait, now it's down to a crawl. OK, so it's something in the house. My wife and I were talking by cell phone, when suddenly I see the dial start its whizzing again. I asked what turned on, and she said, "well, the HVAC started a few seconds ago". Bingo. It's an all-electric home, so we have an electric heater, and when it's running the full system (not just the vent fan), it's really drawing some juice.

The heater is not original to the house (at least, it's a Lennox with logos and branding far newer than the Sears-Kenmore HWH which IS original). I can't tell you it's exact age at this moment. We replaced the filter; no change in electrical use. We REMOVED the filter; no change. We also noticed that despite the massive power draw, the system was not producing very warm air (though it is blowing pretty well). It seemed fine in October/November, but then, we had a relatively mild winter until mid-December. Whatever this is, it is NOT normal; we've had 1000+ sqft apartments and townhomes that we could heat very comfortably in the winter with $150 bills. An extra 500 sqft of house should NOT be costing $300 more to heat. As a reference, through the summer months in this home (including the hottest monthly average for August, ever), which generally produce much bigger bills than winter, we kept this same house around 75* and paid about $220/mo.

We have a home warranty agreement that would cover a fault in the HVAC unit itself, and MAY also cover wiring slipups. We picked a name of an HVAC company out of a city publication for new home owners, so we're not sure just how good they'll be. Knowing what I know right now, what would I expect to hear these guys say? My primary expectation is a short in the heating element or in the switching circuitry within the unit. If they say it's normal I'll be telling them to shove their normal up their [censored]; we've had the HVAC system off since we found the problem, using our fireplace instead, and after living in a house averaging 60*, our latest bill (including the week after the prior billing cycle) was still $250. Whatever it is, it is NOT normal.

EDIT FROM COMMENTS: It is a simple forced-air system with an electric heating element. The breaker marked for the heater is 220V 70A. That means that the max available wattage is 15.4kW. Running 24/7 at its max rated power for 30 days, the system would cost $1020... So maybe, just maybe, there's nothing wrong with it.

EDIT 2: The warranty repair guy showed up yesterday. When my wife showed him the heater unit we had, he knew exactly what she was going to say next; apparently this particular unit is infamous for its inefficiency. Nevertheless, he did a check of the system, and found that one of the 3 heating elements was disconnected. That was putting more voltage onto the other two coils, and decreased the effectiveness of the whole system, meaning we were using the same amount of power to do less work for a longer period of time. After reattaching the element, the house heated up to the thermostat setting quickly and we're noticing it's not running nearly as much. However, we should still be expecting $250-$300 bills for months that hover around freezing.

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I'd suggest editing the question to remove the rant so that it doesn't get closed as non-constructive. Also, be sure to include what kind of heating system. Is it a heat pump, and is it on emergency heat (does the outside compressor turn on)? When you said the winter got cold, what was the average outdoor temperature? – BMitch Feb 14 '12 at 2:31
Where do you live? Have you lived there through a heating season or is this your first one? What temperature do you have the house set at? How well insulated is the house? (I ask as if it's a normally mild region and it's unusually cold, $400 for electric heat seems quite reasonable...but I agree, to save $$$, stick with the fireplace) – DA01 Feb 14 '12 at 5:45
Even if something is wrong with your heater, all that energy ended up somewhere, most likely as heat within your house. So after you diagnose and fix any problems with the heater, go looking for heat loss. Open windows? Missing insulation? Etc. – Jay Bazuzi Feb 14 '12 at 6:23
If your fireplace is not vented with outside air (and I have not seen one in this country that is), using it will increase you heating bill if you expect to maintain 70F in the house. The reason is because a fire will draw massive amounts of conditioned air up the chimney that needs to be replaced with cold air from the outside, through cracks, leaks, vents etc. While it feels warm in the immediate vicinity of the fireplace (stone/brick radiates the heat), keeping the rest of the house warm requires more energy. – cdonner Feb 16 '12 at 2:58
How can an electric furnace be anything but 99+% efficient? – insta Mar 1 '12 at 23:12
up vote 5 down vote accepted

From the DFW comment, I'm guessing you implied Dallas/Fort Worth. If that's the case, then you'll have AC already installed, and a lot of winter days that are above freezing. For that climate, a heat pump would be much more efficient. The emergency heat setting on a heat pump is the same as what you already have and you'll want to use that when it drops below freezing. But all other times the heat pump will be more efficient.

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If your heating system has ducts running through the attic check to make sure one of them has not come loose. Blowing heat into the attic can keep the heater running a lot more than it should.

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