Rapid cooling like this can be a nightmare for full-time RV'ers. In this part of the country, humidity off the Gulf of Mexico from the south is the norm. The front that caused the dramatic cooling came in from the north. This leaves you with warm, humid air inside your RV and cold, dry air outside. That combo is a recipe for heavy condensation. The kind of condensation that, if uncontrolled, leads to, at best, musty odors, discolored walls and shades, or at worst, rot and mold.
The places that need the most attention in these circumstances are the metal frames around windows and doors, the windshield, and outside walls within any cabinets (especially those on slides). You need to be diligent in removing any condensation that forms in these areas or face the consequences.
Once condensation forms, it is imperative that you absorb it fully and not just push it around. I find that paper towels work best as their rapid absorption rates soak up the water on contact. Rags and towels tend to push the water around letting a large amount of water stay on the window, wall or door/window frame or worse fall into dark spaces that you cannot reach.
Obviously, the best way to avoid this situation is to prevent it from occurring in the first place, and since we cannot control the weather we need to control the humidity within our rigs as best as we can.
- Keep internal RV temps cool. Doing so will generally maintain a lower dew point and thus keep your rig dryer.
- Use your air conditioning. Your air conditioner is a great dehumidifier. As the warm moist air in your rig passes through your air conditioner condenser the water vapor condenses on the coils and eventually winds up on the ground under your rig leaving the air inside your rig cool and dry.
- Use your vent fans when cooking, showering or doing laundry. Cooking, showering and doing laundry releases a lot of water into the air.
- Keep a close eye on the weather. If you know there will be rapid temperature changes, you can prepare by avoiding activities that have the potential to add moisture to the air. Take steps such as, avoid cooking, use the shower at the campground, hold off on that load of laundry or go to the laundromat. You can also actively try to remove any current moisture in the air by running the A/C or any dehumidifiers you may have.
As I briefly mentioned above, another way to combat moisture buildup is to use dehumidifiers. We have found a few that work well for us that are compact and quiet, perfect for RV's.
Eva-dry EDV-E-500 Renewable Wireless Mini Dehumidifer - We use this one in our wardrobe. In our Vectra, our entire bedroom slide is a wardrobe. It's great for clothes storage space but having a fully enclosed wardrobe on a slide is a recipe for moisture and mold. If you know there will be a rapid temp change and you have a similar fully enclosed space on a slide-out, it is also a good idea to open any drawers or doors to allow air to flow between the living space and the slide prior to the temp swing. Doing so will prevent drastic temperature variants between the living space and the storage space and prevent moisture buildup.
Eva-dry Electric Petite Dehumidifier - This one we use in our bedroom. It works sufficiently in a space about the size of an average RV bedroom. It is capable of removing 8 oz. of water from the air a day.
Sunpentown SD-652 86-Watt Mini Dehumidifier - We have this one on our counter in the kitchen. It's about the size of a coffee maker and comes with a hose that can be attached to allow it to self drain. Simply plug in the hose, put the other end in the sink and you have a virtually maintenance free dehumidifier for your main living space.
Want an easy way to see how much water is in the air in your rig? Simply take a can of soda out of your fridge and rest it on the counter for a few minutes. You can quickly judge your moisture risk level by observing how much "sweat" forms on the can. A few drops and you're probably OK. A puddle and you had better start taking some steps to reduce your moisture levels.
As the old saying goes, "An ounce of prevention is worth a pound of cure."