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herbhofmann's avatar
herbhofmann
Explorer
Oct 17, 2013

Condensation In TT on Cold Mornings

My DW and I went on our first October camping trip and first night out when it was cold enough to get condensation inside the TT.

Question: What is the best way to prevent this? Not only the windows were wet, but also along the aluminum framing. Our first TT was Stick and Tin (and old) so we never camped this late in the year.

My thinking is to keep the trailer a bit warmer at night (DW likes it COLD) and keep the vents open (got Maxairs on order). What do ya'll think?
  • The main thing to help with the condensation is air flow. Very important to give that moisture an outlet. Try keeping the roof vents open. That's what I did.
  • When people breathe in small spaces, they add to the humidity level. Propane heat always causes humidity problems. Keeping a vent slightly open helps. Ultimately being able to use electric heat and avoiding the propane furnace would be the best bet. Unfortunately, most campgrounds frown on electric heater usage even though they are probably charging you close to the same rate that they would in the Summer if you were running 2 - 15k AC units!
  • I have found it helpful to keep bath vent open in bathroom and vent fan on when cooking or showering.
    During the night, I always run the roof ac fan (fan only) with propane furnace running. It is important to have air moving and at consistent temps throughout cabin. This doesn't eliminate condensation especially on windows but helps.
  • Seeing your from Keiser and coast camping, you've experienced first hand the issues with Oregon coast camping in the fall, and winter is even worse.

    Basically you have two choices to solve your problem, and it IS a common problem at the coast, your not alone.

    Both choices require keeping the interior surfaces above the dewpoint.

    first is like some mentioned above with heat and ventilation. Second is to lower the RH so the interior surfaces never get below the dewpoint.

    we had similar problems in western oregon in the fall/winter. Our solution is to run a small portable dehumidifier in the trailer when we have full hookups. with this setup I set the thermostat to 45F (the lowest it will go) at night and we NEVER have had condensation problems, just let the dehumidifier run all night.

    Go to Freddy's WalMart, Bimart and see what they have on sale this time of year. go for small so it doesn't take up to much room.
    they are easy to empty.


    Just make sure it is a real dehumidifer, one with a compressor. They are basically a refrigerator with the coils exposed to the air, to condense water out into a bucket. And then they provide a small amount of heat and air circulation as well. It will take gallons of water out of the air every day, and completely solved the problem for us.

    Now when we dry camp, another story, since running the dehumidifier isn't an option It's ventilation, ventilation, ventilation and keeping the temps up at night.

    A couple of things to be aware of as far as moisture. When your using the gas stove or oven, for every gallon of propane you burn, you will put about 3 quarts of water into the air. Add to that water vapor when you boil water or cook. don't worry about the forced air furnace or HW heater, all it's combustion air vents outside and won't add moisture to the interior air.

    IMHO if moisture is a problem probably one of the worst things you can do is run a non vented propane heater inside the trailer. (cat heater or whatever hydrocarbon CxHy +O2= H2O(water) + CO2 + heat) Now your again adding 3 quarts of water for every gallon of propane your burning for heat.

    And people actually add a fair amount of moisture to the air every day just from breathing and perspiration. Along with any wet/damp clothing. It all adds up in a hurry in a relatively confined space.

    and ALWAYS have a vent fan on when using the shower.

    A problem we run into is that in the fall/winter on the coast outside RH is near 100%, so even though RH drops rapidly with temps, ventilation will help under these conditions, but the air coming in isn't at all dry and doesn't always completely solve the problem.

    PM if you have more questions.
  • Best solution to preventing condensation is to open a vent or window enough to bring in some cold air and effect the relative humidity inside the RV. Windows may NEVER be completely condensation free because it's the cold glass on one side and the warm inside of the RV on the other and it simply is the FORMULA for creating condensation. Double pain windows would help quite a bit but even they sometimes condense a little.

    We always keep a relatively NEW windshield squeegee in our RV and use it to remove moisture from the windows. You can pick these up at Walmart for only a few bucks.

    Good luck / Skip
  • loulou57 wrote:
    We had the furnace on in the TT the last week of august.

    The first night we had no heat and closed the vents...we had condensation. We then turned on the heat, left the vents open and had no problem. We know heat goes out the vents but we always have a window open in the bedroom in the winter.


    Exactly as loulou said. Keeping the vents open with heat set should solve the problem, that's the nice part of the maxxair covers.
  • We had the furnace on in the TT the last week of august.

    The first night we had no heat and closed the vents...we had condensation. We then turned on the heat, left the vents open and had no problem. We know heat goes out the vents but we always have a window open in the bedroom in the winter.