Size Matters, and Bigger Isn’t Better
With a provocative title like that, you’re sure to be disappointed by the realization that I’m talking about air conditioning equipment, and not, well, something else.
With the dog-days of summer upon us, and temperatures in my part of North Carolina pushing 100 degrees, I’ve been thinking a lot about AC. I’m always trying to keep my power consumption low by setting back my thermostat during the day, but in the hot and sticky south, I’ve got to keep my eye on the house’s humidity levels. If they stay too high, or the temperature cycles up and down frequently, I could get moisture and mold problems.
Which brings us back to our discussion of size, and why bigger isn’t better. According to Energy Vanguard, an air conditioner that is too large will cool your house very quickly (sounds good!) which means it doesn’t have the chance to dehumidify the air (sounds bad!). In fact:
If the AC comes on, runs 10 minutes or less, and then shuts off, the house may be cool, but in a humid climate, the indoor humidity levels will stay high, probably over 60%.
To tell if your air conditioner is oversized and your house has the potential for moisture problems down the road, you can either get a thermostat with a humidity sensor, or,
Just get your stop watch and time how long the AC runs on a hot afternoon. Ten minutes or less, and it’s definitely oversized. Twenty minutes would be OK. Thirty minutes at a time or longer, and your humidity levels should be fairly low.
At this point, most of you are thinking of jokes about how longer is better. Just get your mind out of the gutter!
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