On Mar 22, 12:03*am, jeff_wisnia
wrote:
Over the years I've had a few thermal fuses in houshold appliances go
open for no apparent reason. When I've replaced them with ones with the
same temperature rating they stayed working fine for years more.

A couple of days ago our three year old Bunn coffee maker quit, because
a 141 degree celcius overtemperature thermal fuse on the water tank
opened. It might possibly have happened because the water tank
thermostat stuck closed, but after I repaired it the thermostat cycled
just as it should.

I was suprised to find that there were TWO identical thermal fuses
connected in series located right next to each other, the bodies were
actually touching. That seemed like a belt and suspenders approach,
unless there's a significant likelihood that a thermal fuse won't open
when it should?

Comments?

Thanks guys,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10e12 furlongs per fortnight.

I had one of the hot water dispenser tank settups that goes
under the kitchen sink. A few years in, it failed due to the
thermal fuse failing for no reason. The original was no longer
available and had been replaced by a different type of design,
attachment method, etc. Looks to me like they had a
problem with them and changed the design.

I would suspect that part of the problem today is a lot of
the thermal fuses are being made in places like China with
poor quality control.