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jeff_wisnia[_2_] jeff_wisnia[_2_] is offline
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Default Do thermal fuses fail from old age?

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.