Many good tips! Yes, the thermostats and fan settings are all where they should be. I don't think it's low refrigerant -- the a/c works great, until it ices up, which takes a while.
I should remove the interior air distribution box so that I can see the evap coil from inside the trailer. If it looks bad, then I will have to think hard about going back onto the roof and opening up the plastic box that surrounds the evap coil.
I like the idea of using aluminum tape to re-seal the box -- assuming that it does not shatter while we are trying to open it.
Now for the hard part -- persuading DW to participate in this next experiment in DIY A/C maintenance.
