Timer for the dryer doesn't work properly on "Timed Dry". I normally set 45 minutes and turn "start". But recently it doesn't start after I set 40 or 45 minutes. I try other time, such as 30 minutes. Sometimes it starts, but stops before it comes to end, so the cloth is still wet. And sometimes it is still running after timer knob passes "off". I don't know how long it has been running. Is there something wrong with the timer? Will the problem be solved by replacing a timer and how can I replace it? Thanks a lot.