If it's electric, it Could be that you've lost one leg of 120v.
Electric dryers are 240 volts for the heating element, but the tumbler motor and electronic control is 120 volt. Could be a bad breaker, or loose connection.
My father in laws mom had this issue when a contractor accidently cut the wire which powered the dryer outlet. But they only partially cut it through one of the hot wires.
So she assumed the dryer went bad, bought a new one and had it installed only to have the same problem.
I'm an electrician so I went over and found the problem.

They lose their rated output after 25 supposedly, the problem with solar pv right now is that manufacturers might not be around that long as so many companies are pumping them out and the cards haven't fallen yet on who will still be in business in a couple decades.

The same thing happens in the lighting industry, cfls, LEDs, any hot technology has a bunch of manufacturers enter the industry and after a while most close their doors leaving the customer with a useless warranty