DIYbanter - View Single Post - Diff between a $20 and $100 1500W space heater

Dave Martindale

writes:

I was never convinced because I know that you only get a set amount of
heat from a set amount of electricity. But lets answer this once and
for all. Its got a ceramic core, but isnt there still a glowing wire
inside that core? If not, how do they work?

It does have some sort of resistance element in there to convert amps
into heat. But the resistance element is part of the ceramic "core"
which also contains many passages with air flowing through it. The
heat from the resistor is conducted through the core to a large amount
of surface area for transfer to the air. Because of this, no part of
the heater core gets very hot. It might still be capable of burning
your skin if you touched it directly, but there is nothing that glows,
nothing hot enough to start most combustibles burning.

So it's no more efficient than any other resistance heater at converting
electricity to heat. But the low temperature makes it safer than the
glowing-wire heaters, and the heater core with lots of little air
passages probably makes it easier to add a fan and direct all the warm
air in a particular direction.

Dave