Condensation on upper inside walls ral cold morn

Last night we left the bath vent open 2 “ and used the small electric heater
Kept it at 70 inside, rained all night temps in the 40s , didn’t feel any dampness at the top of the outside walls
Even the other day it was just slightly damp about an inch from the ceiling
Thx

Lynnmor wrote:

mike-s wrote:
Get a small dehumidifier.

8 oz. per day under extreme conditions. Much more is needed, so a compressor type of dehumidifier is needed.

x2. If you have a humidity problem that is visible, this isn't going to help. As mentioned in a previous post my compressor dehumidifier usually will pull 5 gallons of water out in the first 12 hours of operation when we go to the oregon coast. After that 3-5 gallons/day is typical.

I have had the vent in the bathroom open all day.. Its 49 our and no condensation since we turned the heat up after waking
The furnace hasn’t come on today because we have a small electric heater that comes on and off with a fan
It doesn’t seem to run much either right now
I’ll leave the bath vent open tonight ... the door of the bath is open at the top

Yep. you got to either open a vent, or crack a window. The inside has to have air. Often times. If you don't crack a window, or vent the air in your bedroom. It can actually rain on you from the ceiling.

mike-s wrote:
Get a small dehumidifier.

8 oz. per day under extreme conditions. Much more is needed, so a compressor type of dehumidifier is needed.

Cold corners will condensate. Using your furnace to heat and a fan to keep air moving should help. Running the A/C when it's warm enough will remove moisture from the air. We have at times run the furnace, let it warm to 78 or so and then turn the A/C on and cooled it back to 70. We have a humidstat so can see that the amount of moisture is being reduced by doing this. Other things we do -- wipe down the shower after use - put towels outside to dry. Don't leave dishes sitting in the sink filled with water. Reduce cooking that involved boiling things like pasta, rice or potatoes. We also use Damp Rid containers in small enclosed areas like under the dinette seats, closets, and under bed storage areas. They collect a surprising amount of water and need to be changed out every month or so. We also do not open windows or vents when it's cold - counter productive to trying to heat the place.

We lived in a 30' 5th wheel trailer with a 13' slide for one winter while our house was being built. Typical rv trailer with 2" thick walls and R7 roof/walls and floor.
Temps would get down to zero for a couple of days with 40 mph winds for days. The colder it got the worse moisture issues were inside the trailer and especially inside the closets/cabinets.
Were first tried the vents and windows open combinations and three fans moving air but all that did was cause a very cold drafty camper.
Finally dropped by the local KOA campground and talked with a few full timers how they delt with moisture inside the trailer.
All said the same thing....get two dehumidifiers for a 30' trailer.
Worked great. These two units were whisper quiet.
It was surprising how much water we dumped daily from them.

I keep my current trailer in the trailer shed. It has one side open to the south.
I keep one roof vent cracked maybe a half inch open.

Now my son lives in FL about 25 miles from the coast. No way he could leave a window or vent cracked. He puts out a couple of containers of DampRid then checks them per instructions.

No one mentioned it but the average person exhales about 1 quart or more of water vapor while sleeping. That is why in cold weather tent walls and ceilings will be covered with condensation in the morning and sleeping bags will be damp on the outside if a tent window is not left unzipped at the top to allow moisture to vent.

I stored a trailer in winter in Seattle, outside. I found that a slight amount of heat, like 55°, kept the inside stink- and moisture- free.

Just so it doesn’t get stale I guess