On Sat, 24 Mar 2012 18:55:44 -0400, jeff_wisnia
wrote:

I'm finding it somewhat hard to believe that the warmer heater would
overheat, since there's no thermostat in or on it which could fail in
the closed mode and cause such overheating.

UL coffee maker standards:
http://ulstandardsinfonet.ul.com/scopes/1082.html
http://bbs.dianyuan.com/bbs/u/33/1127541096.pdf
Section 18.x for thermal cutoff requirements.
Section 23.x for whether a thermal cutoff is required.
Table 33.1 shows the maximum temperature rise allowed. As I read
between the lines, any part that might rise above the stated
temperatures, requires a thermal fuse.

UL 60691 for testing of the thermal fuse:
http://bbs.dianyuan.com/bbs/u/32/1122972217.pdf
Section 10.8 discusses its use as a short circuit protection fuse.

You might find this interesting:
http://www.fixya.com/search/p89511-bunn_nhb_coffee_maker/thermal_fuse
It's a different model Bunn coffee maker, but the problems are
probably similar.

I'll await comments from others regarding the need and/or usage of a
thermal fuse on the warmer.

Ah, truth by consensus and acclamation. Much as I like the concept,
I've seen it fail far too often.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558