Air Vents

• Mud nests in vents by Mud dauber wasp (apparently common in southwest): tape over the vent if not in use (and place sign next to switch to remove tape before starting appliance).
• Rotating Holding Tank Vent - or just PCV "T" pushed over the top of the stack on the roof. Be sure the "T" is sideways, that is the air should NOT be able to whistle thru the "T"
• Isolate vents in cold weather - and also in hot.
• swamp coolers If you are in an area with very low humidity (AZ). Unlike air conditioning where you close up tight, swamp coolers bring in outside air which is cooled by water and you leave a window/vent open to circulate the air. It seemed that AC just didn't work when there wasn't humidity in the air. They are also available in portable models which can be handy for a small space and that way they do not have to be installed and you just handfill the water supply. They are often called "personal" coolers. In rainy weather they do not work as you just sort of steam.