Hi - I recently bought a new home and it has a harman p68. I used it pretty frequently over the winter and, today, it just stopped working…It was going fine and, then, I noticed that it had stopped…I tried to turn it back on and it makes a noise like it's planning to start, but, then the fan doesn't go…In looking at the directions, it stated that sometimes it needs to be re-set by unplugging it…So, I did that…I was then able to start it, but it shut down again after about 20 minutes….The previous owners left the manual and a receipt from last year stating that the control board was replaced…Does this sound like a motor? Can it be fixed? I'm not sure how old the unit is….I'm guessing at least 6 years, but possibly older…Thanks for your help!