smbisig
Adventurer
In cold nights in the PNW, whether raining or not, you'll have a nice layer of condensation inside the entire camper. The benefit of having the fan is to be able to close all the windows and pull out the condensation. You can get by with just having a heater of some sort (one that separates hot air vs. exhaust fumes (diesel heater, etc.)) and just wipe down your whole interior.
That being said, after owning a camper with no fan, I'd never buy a camper again unless I could have a fan.
Knock on wood.. I actually haven't had to deal with any noticable condensation here in Western Washington. Several nights camping below freezing. However, I do have a dickinson, so lots of dry heat being produced throughout the night.
I have also installed the GP Factor vent, but this is for when the tent is closed.
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