My Whirlpool range's broiler element exploded.
The range is 4 years old and has had very little use.
I was baking a pizza and decided to brown the top so I turned on the
broiler.
I left the oven door ajar and within 30 seconds there was a loud bang,
a flash
of light and a portion of the element was burning brightly (like a
welding rod).
It appeared that the element was melting as burning bits of it
dripped onto the
floor of the oven. I turned off the breaker and the fire went out.

The service tech changed the element (which showed that indeed, the
element
had melted almost to its core) but the element won't heat up. He
removed the
back cover of the range and visually examined the circuit board. There
was no
evidence of damage. The display panel works, the oven element works,
the surface burners work; when set to broil, the display shows 500
but
the element doesn't heat up.

The service company, of course, doesn't cover circuit boards and they
want $250 for the part.
#1. Shouldn't the breaker have tripped?
#2. Shouldn't the display indicate a malfunction?
#3. Whirlpool 800 number wait time is always at least 30 minutes.
#4. If it's a burnt out component on the board, shouldn't I be able to
see
some indication -- such as a burn mark.

The range still works fine except for the broiler.
Thanks.