North Georgia hasn’t been horribly cold this week, but the chill still creeps in. Bumping the thermostat up a couple of degrees would help, but heating the entire home isn’t economical for just sitting in one room. A space heater can help.
Space heaters come in many shapes, colors and price classes. Electrically, though, there isn’t much difference between them. All the off-the-shelf units in the stores are of the resistance-wire type. In principle, this kind of heater is like a large light bulb. Electricity flows through a wire that’s just slightly too thin to handle the current comfortably. It heats up to a red glow. Old-fashioned incandescent bulbs do that with an even thinner wire, so they glow much brighter.
This consumes a good deal of electricity. Check the box labels: the maximum setting on space heaters is 1500 watts. Making them more powerful than that would upset standard home circuit breakers, which allow for 15 amps to flow before they cut off. Some circuits are stronger, but for safety reasons it is assumed that the wall outlets are the 15-amp type and not higher. This allows for roughly 1600 watts to be drawn, which is equivalent to one space heater plus safety margin. It’s OK to add a small power consumer on the same wall receptacle or another outlet in the room. Plugging in the Kindle or a cellphone charger won’t make a big difference. But a second space heater will. If the breakers in the main panel are modern, they’ll trip as a warning. Old ones may be slow, allowing the outlet to heat up greatly while all that electricity is trying to shove its way through. Eventually, a meltdown and fire are likely. The Times reports many house fires this season. Never try to run two heaters from the same power outlet.
The safest space heaters tend to be the oil-filled type with the big ribs. There’s no exposed hot wire, and no fan that can suck in flammable dust and blow it past the glowing wire. Some advertisements promise miracle devices, using fancy words from a science textbook. But when purchasing a space heater, keep in mind that in every case you’re getting a wire heated by electricity. Just like buying a new car, you decide how much the extra visual bling-bling is worth to you.
Rudi Kiefer, Ph.D., is a professor at Brenau University, teaching physical and health sciences on Brenau’s Georgia campuses and in China. His column appears Sundays and at gainesvilletimes.com.