i have a pansat 2700a,
and have had simular problems.
i did lots of research on the web for it, and found out that there are a couple capacitors inside on one of the main circuit boards. perhaps one for vertical channels, and one for horizontal channels, ect...
anyways, when they made the reciever, they didn't put in big enough capacitors.
i bought two new ones from a local tv, computer dealer, with higher ratings, and soldered them in.
my problems went away.
very rairly do i have problems like this again, and if so, it is perhaps because i am trying to tune in another network, and my settings aren't quit acurate in the menu, or the dish needs to be alighned slightly more to the east or to the west.
if the problem does happen, i just do a cold reset i beleive its called, by unplugging, and replugging in the reciever.
but this rairly happens, after i installed the higher rating capacitors.
the reason for the fan(s) on there is probly because the capacitors are running to hot, and shutting the sytem down.
you need capacitors with a higher temperature range,/freque..range i would beleive.
hope this helps...