On Tue, 11 Dec 2012 08:14:54 +1100, Franc Zabkar
wrote:

On Mon, 10 Dec 2012 02:04:06 +0000 (UTC), Ian Malcolm
put finger to keyboard and
composed:

I assume you are in 120V land!

A simple calculation (P=(V^2)/R) shows the resistor probably dissipates
72 watts which would correspond neatly with your observed 78W draw.
However the originals are only rated for 20W - no wonder they fail!

You do not know what extra testing has been done by "Helen of Troy" to
qualify these resistors for use at 3.6 times their rating, nor do you
know if a third party's 20W 200 ohm resistor will fail safe.

I'd like to see how these appliances behave if you operate them
without a water load. Do they actually sense the presence of water
and, if not, is the bimetallic switch able to prevent damage to the
resistor in the absence of cooling?

- Franc Zabkar
Yes Franc, there is a bimetal switch in series with the resistor and
it lays along the length of the resistor.
Eric