How to deal with condensation

[JanetG]

Hi All, We are new RVers, we have a 2020 25' Flying Cloud FBT. We love it. When we are camping in the colder weather, like last weekend in Vermont, we get some condensation on the inside of the windows during the night. Daily temps were 50-60 during the day and 35-45 overnight. We typically run the furnace when we get up in the morning and a little bit at night before going to bed. I've started running the stove fan vent when making coffee in morning and cooking, but we get condensation even without cooking. We normally have the shades down and curtains drawn at night. Any tips to minimize or eliminate the condensation? Thanks so much for your help!

[Fungus]

Current thread in deep discussion regarding condensation:
https://www.airforums.com/forums/f45...on-238142.html

[RickBullotta]

Originally Posted by JanetG

Hi All, We are new RVers, we have a 2020 25' Flying Cloud FBT. We love it. When we are camping in the colder weather, like last weekend in Vermont, we get some condensation on the inside of the windows during the night. Daily temps were 50-60 during the day and 35-45 overnight. We typically run the furnace when we get up in the morning and a little bit at night before going to bed. I've started running the stove fan vent when making coffee in morning and cooking, but we get condensation even without cooking. We normally have the shades down and curtains drawn at night. Any tips to minimize or eliminate the condensation? Thanks so much for your help!

Doesn't yours have Fantastic Fan vents? Run both and maybe even the bathroom fan. Run them when you're cooking also (in addition to the hood vent).

[Daquenzer]

Originally Posted by JanetG

Hi All, We are new RVers, we have a 2020 25' Flying Cloud FBT. We love it. When we are camping in the colder weather, like last weekend in Vermont, we get some condensation on the inside of the windows during the night. Daily temps were 50-60 during the day and 35-45 overnight. We typically run the furnace when we get up in the morning and a little bit at night before going to bed. I've started running the stove fan vent when making coffee in morning and cooking, but we get condensation even without cooking. We normally have the shades down and curtains drawn at night. Any tips to minimize or eliminate the condensation? Thanks so much for your help!

You can also get a dehumidifier. There are some made specifically for campers. I have found that running the LP furnace at night also helps to circulate the air. Otherwise you have dead air which is not good for condensation.

[Tim A.]

As I posted in the thread cited above, ventilation can help greatly to avoid condensation inside a trailer. No matter how low the temperature, we have one window and one roof vent cracked open in our 19'. We do that in sub-freezing temperatures with the furnace running. It helps remove inside, moist air and replace it with outside air. Here is what one internet source says, "One person asleep adds half a pint of water to the air overnight and at twice that rate when active during the day."

The volume of air inside a trailer is very small, so just breathing can add considerable moisture to the inside air.

Tim

[waninae39]

It's best to have cross flow air to evacuate moist air. Window open on one side, fan on the other

[uncle_bob]

Hi

Simple summary:

1) Save energy, keep the windows shut, get condensation.

2) Use more energy, keep windows / vents open, get less condensation.

If you are off grid and running on propane, the answer is often to save energy.

If you have two large dogs and two to four folks in the trailer, it doesn't take any cooking to get into condensation issues .... If it's high humidity outside / raining ( welcome to Alaska ....) coming up with ventilation can be a challenge.

Bob

[cazual6]

Crack a window open. Here's what I do.

I keep shower and bathroom vents open. If there is still condensation, then I crack open one or both of the vents. How much to crack open depends on your satisfaction.

[LNBright]

PO put maxair covers over our fantastic vents. Thus, I just leave our roof vents open all the time: the covers keep the rain from blowing in, if it's rainy. When it's not, they're fine to have open. (I guess if we ever camp when it's terribly cold, I might close them, but, our trips thus far haven't required such.)

[AnneFitz]

We have a 2018 25 ft fbt and we are currently living in it while our new house is being built ,2 adults and two dogs in the NC mountains , I purchased a small dehumidifier from Amazon and it works well , I may order one for the kitchen area [
Seavon dehumidifier 27 oz capacity . It it very compact and very quiet , 2 other airstreams in our park also use them

[BigSxyWhtGuy]

We tried the little dehumidifiers and it filled overnight. We switched to a larger 30qt one. No more moister on our windows. Only down side is it’s much larger and needs to be transported. It fits perfectly under our dinette though. We also know we can use this in our future home too when we are done traveling.

https://amzn.to/3rgAkCt

[PatLee]

Without turning your fantastic fans on (unless you want to), just crank open the lids a couple of inches when using propane heat. No matter what you've set the temperature for, propane heat comes on nice and warm right away; so releasing some of it through the fan openings moderates the sudden temp change between the warm air and cold windows. At least that's my theory and it works for me. I also rest some of the windows on their latches (in closed position so there's an opening about an inch wide.

[JanetG]

Thanks so much to you all! Really appreciate your time to answer and the wisdom. We leave for Acadia (Bucket list trip for both of us) this weekend so we'll test it out! Not enough time to get a dehumidifier but will try the windows or fans open.

Thanks again.

[Bob Peahl]

We keep the bath and shower vents open, one on, one off.

Also, keep an eye on the beds-condensation will build between the mattress and wood surface. We installed Hyper Vent Moisture Barrier material. Works great!

[Steamguy]

Originally Posted by PatLee

Without turning your fantastic fans on (unless you want to), just crank open the lids a couple of inches when using propane heat.

^^ This. Combine it with a cracked-open window, and no worries. We've been doing this for over 30 years, and it really minimized the condensation problems. The only times we got condensation after that was when it was really cold and humid outside. Even then, it was a matter of opening the window and vent just a bit more.

One note: the Fantastic fan lids are well-designed and shed condensation water nicely onto the outside of the trailer. Some other RV vent lids do not.

[uncle_bob]

Originally Posted by Steamguy

^^ This. Combine it with a cracked-open window, and no worries. We've been doing this for over 30 years, and it really minimized the condensation problems. The only times we got condensation after that was when it was really cold and humid outside. Even then, it was a matter of opening the window and vent just a bit more.

One note: the Fantastic fan lids are well-designed and shed condensation water nicely onto the outside of the trailer. Some other RV vent lids do not.

Hi

If you do this on our trailer, you get an added "feature" head into the bathroom and you get a nice drip drip drip shower as you do your thing. You also have a puddle on the floor to wash your feet in .... ( = the moisture condenses at the vent and drips back inside ....).

Bob

[JanetG]

Thanks to all who gave advice. We cracked the window and/or the fan and it worked perfectly. Very happy to have this great group as a resource.