I purchased my Whirpool dryer new from Sears about 5 years ago. It works
well, except that while running, it emanates a fairly loud BANG every 20
minutes. It's electric. It did this in my previous home, moved, and does
it the same in my new home. So I think I can rule out electrical
problems. It has good ventilation, and I also clean out the dust filter.
The sound is muffled inside the metal structure, and is similar to a
large piece of metal popping from expansion. I thought this was the
reason but it does this about 3 times during a drying session.
Also, I noticed there is an area near the top of the dryer in the back
that is turning black as if a lot of heat is back there, which is
reasonable since it gets hot while running.
I never run major appliances while not home, except the fridge of course.
Any experience this?