Condensation in your Escape

[cpaharley2008]

After spending 3 days and nights in below freezing temperatures I have made the following observations. There were 3 adults and 2 large dogs, so let's just say 4 adults. The electric portable radiant fan heater seems to create more condensation than the factory propane heater. With the kitchen window cracked and the MaxxAir open, there was still some wetness around the bed and dinette walls. At first my plan was to install some reflectix between the bed and the exterior walls but upon further thought decided another approach.
I plan on drilling small holes around the inside perimeter next to the exterior walls of the bed and dinette wooden support base, about every 2". I'm starting with the dinette first for ease of access. My feeling is to create air movement from below the bed/dinette that would help dissipate the moisture. Perhaps even moving the electric fan heater under the bed which would create air updrafts around the bed perimeter. With the front dinette, installing small intake vents should allow air movement within the compartment to exit thru the holes. I came to this conclusion after feeling the refer wall, exposed to the outside thru the vents, yet there is no condensation along that wall next to the bed. I think it is because there is a lot more air movement within that compartment.
The windows really did not sweat when you left the blinds up a little at the bottom. I plan to install some reflectix between the front window protector and the single pane front window.
The bath window and ceiling vent has been covered with foam and there was no sweating there, particularly with the door having a vent and air movement.

I really think that air movement is the solution for winter condensation, what are your thoughts?

[float5]

Did you run the electric heater all night? We don't run one while sleeping and I have seen that others do not also. Just saw someone who said they rely on the furnace only, at night. You have too much condensation because of too much heat. Cracking the window may not be enough. But there are people who just wipe the walls down from such condensation.

Also, on the Reflectix, that kind of stuff is generally only to be enclosed as it is an outgassing type of problem with heat. It probably should not be out in the open. Don't know for that particular brand. Guess you decided against it anyway.

I don't think I would go to the trouble you are contemplating unless you try something else a few times.

[JimJ]

There was a good thread about condensation last March: Wet Bed - Escape Trailer Owners Community. Some of the folks posting said they had good luck with dehumidifiers and provided links to the ones they used.

[daveandsandyclink]

Don't take this wrong Jim but............................................... ...........
My solution...Maybe stay at home when a blizzard is coming!
That solves condensation, frozen pipes, and traffic accidents.
To each his own. As for me...I don't like being trap inside a small trailer for more than a day. Especially with two large dogs and my wife.
Was this a test of your trailer cold weather performance or do you just like camping in snow storms?

[DonM]

I am having venting installed at the factory (2 vents- one high and one low) in all my enclosed storage boxes, in order to create air flow. My primary concern was heat in the Driver side dinette seat where the converter and Inverter are located. Heat damages electronics. I think the same principle applies to condensation avoidance.

[Dave Walter]

A few words on rv condensation.

[QUOTE]When it gets cold and dark outside, the last thing you want is dank, cold, and dark inside. But an RV does not present an easy task for environmental control, especially of humidity. So condensation on the inside can be a problem in an RV when it gets cold outside. This condensation can be as bad as a water leak when it comes to the possibility of damage to the RV.

In order to get condensation, two factors have to work together. The first is evaporating moisture into the air and the second is changing the temperature of that air enough to cause the moisture to condense back out of it. In between there is the movement of air caused by various mechanisms such as convection and moving objects (such as people).

Sources of moisture in an RV

Perhaps the most important sources of moisture inside the RV are washing, especially with warm or hot water, and combustion such as in the use of the stove and refrigerator or auxiliary heaters. People also tend to contribute quite a bit of moisture as well. If the air is cold, you can see your breath as its moisture condenses. When the air isn't cold, the moisture in your breath contributes to the humidity.

Since an RV is a confined and small space it won't take a lot of moisture added to the air within it to load up the air with moisture. Activities that add moisture also tend to make the air warmer and warmer air will hold more moisture.

Where will it condense?

There are obvious places where condensation will occur such as on single pane windows as the glass is not a good insulator and will be near outside temperatures. The frames of windows, if made of metal, may also prompt wetness. Condensation can also occur in other places, too. Have you ever looked at the metal parts around the refrigerator burner and wondered why they looked so rusty (or your automobile tail pipe!). Also inspect those hidden areas in your RV where the air is relatively still behind a couch or cabinet near the corner of the floor and an outside wall?

What to do?

Ventilate! To reduce or prevent condensation you have to remove moisture. This means moving air that is likely to be nearing its dew point to somewhere else so it can increase its temperature or mix with air that has a bit less water vapor in it..

When washing in the kitchen or bathroom, crack the window or turn on the vent. Yes you may waste some heat but you will also greatly reduce the moisture in the RV.

Keep absorbing (think rot) or reacting (think rust) materials away from places where condensation may occur. Water soaking into wood or cloth over time may cause rot or other unpleasant deterioration. If things do get wet, make sure they get dried through and through as soon as possible.

Provide a means for any water that does condense to escape. Provide some sort of drain to allow any condensed water to run off to someplace where it can dry out or not cause harm.

The air conditioner and the refrigerator

The typical RV rooftop air conditioner refrigerates air by passing it over cold pipes. Your refrigerator works by putting cold pipes in the insulated box. In both these cases, water can condense on the cold pipes and may even freeze on the pipes. Air conditioners usually just drip this water down the side of the RV, which may cause unsightly stains. Refrigerators will usually freeze condensed water so that you will need to defrost your refrigerator occasionally.

The swamp cooler or evaporative cooler works in just the opposite way. In dry climates where the air is warm and the humidity is low, you can put water on a pad and blow air through it. The water will evaporate which causes the air to become cooler and more humid.

To evaporate water, energy must be added to it. This energy comes from the surrounding air, which makes this air cooler. To condense water, energy must be taken away from it. This means that water condensing on something is trying to warm that something up.

A note on measuring water in the air

Water is normally a liquid or solid at temperatures we can live in but it evaporates to a gas up to a point where the water vapor tends to push back and limit further evaporation. The two main factors that limit how much water vapor can be evaporated are temperature and the amount of water vapor currently in the air. Meteorologists measure both of these factors to be able to determine what the moisture in the air (water vapor) might do. Relative humidity is the amount of water vapor in the air as a percent of the total amount possible. The dew point is the temperature at which the water in the air would hit maximum possible amounts and start to condense. For any chunk of air, its relative humidity will depend upon its temperature while its dew point will remain constant.

You might note that a very cold, dry winter day might have a high relative humidity. This is because cold air cannot hold much water vapor so what it little has is a high percentage of what it can hold. When this air is moved into your RV and heated, its relative humidity will become very low as the now warmed up air can hold a lot more moisture. Whether the air is hot or cold, its dew point will stay the same. When the temperature gets down to the dew point temperature, you begin to see things like fog or pogonip.

/QUOTE]

Cheers
Dave

[Jim Bennett]

Electric heat will not add any condensation at all, and either will the propane furnace that vents all burned gases (and associated moisture outside. The fridge and water heater exhaust is vented out, eliminating them as a source of moisture. Pretty much the only appliance that releases water vapour is the stove.

People breathing by far is the number one source of moisture in the air in the trailer. This moisture will condense on a surface substantially colder than the air.

As you were thinking Jim, the only way to rid this air borne moisture is through ventilation. Keeping windows cracked, and even the fan on low helps. Warm air will hold more moisture than cold air, allowing it to vent more moisture when moved out.

We have spent many a night at temps a bit below freezing. When boondocking, we keep the temperature around 5-10°C, and sleep with a lot of blankets. We do keep a vent open, not never run the exhaust fan. A few times in the morning, we have wiped down windows and frames, but that was the extent of dealing with dampness. There is usually only two of us, and one dog.

When in campgrounds, we keep the heat higher and with a vent open, never have condensation issues.

It is best to keep blinds open, as they insulate the windows, allowing them to cool off more, and when open, allow air movement by them to keep the condensation cleared off.

I would be really cautious of adding another layer of insulation, unless it was sealed airtight, as this would allow it to be cooler behind this layer, and give a place for condensation to form.

[cpaharley2008]

I purchased 25' roll of reflectix awhile back and today I installed it around the bed and cut a piece for the front window. It is 16" wide x 25' so had enough. I doubled it over to fit the 8" thick bed perfectly around the perimeter. Had enough for the bed and front window and dinette cushions (single ply as they are 4" thick). Will camp in the driveway to test and report back. If positive I'll post pictures.

[santacruzer]

I used Reflectix when I had a pop-up, and it was especially helpful under the bunk-end mattress pads, since those hung out over the ends and had virtually no insulation from the elements. It might not be as insulating inside a trailer, since there's a lot of cabinetry space involved under the seat covers. I'd be real interested in hearing your results!

Also, I found that even with Reflectix in the windows of the pop-up, there was still condensation between the Reflectix and the window...not as much, but some. It was most helpful in retaining the heat in winter, and reflecting it off in summer.

[cpaharley2008]

In the Escape 19 there is a front window awning guard that closes on the window, I put the reflectix inside that space, on the outside between the guard and the window. Will report back with results.

[float5]

santacruzer, when you mention condensation between the Reflectix and window, I have seen a window that was a real mess from similar stuff. Over time it ruined it. Anything next to a barrier like that will have had so much condensation eventually that it makes a mess of it. Reflectix cannot take care of the problem of too much heat and not enough ventilation. In fact, it will likely make the problem worse. Of course, a pop-out would get much more air, I would think.

As First Jim mentioned, you need lots of blankets! And ventilation. And as he said, breathing is the big source of the problem. Someone gave the surprising stats on that a while back. If a microwave is available, it is good for heating water to keep the condensation down.

Also, I understand that a new trailer has materials which cause more condensation the first year, just as a new one has outgassing. May not be as bad the second year.

[cheryls]

Along with using a dehumidifier and keeping the Maxx fan vent open a bit in our 19', we found it really cuts down on moisture around the bed if we keep one door to the under-bed storage open when we're camping in cold, wet places. Otherwise it gets very cold under there and very warm when two people are lying in the bed, hence increased condensation on the walls around the bed and under the mattress.

[hotfishtacos]

Would anyone comment on their experience with de-humidifiers? We just got back from a trip that was cold and rainy and had way too much condensation going on inside the trailer around the windows...dripping where it shouldn't. I would like to find a good solution for this. Thanks!