Condensation Problem

[Festus2]

A couple of weeks ago, I went to carry out a routine inspection of the inside of our 5th wheel. While checking the bedroom and bathroom area, I noticed a very fine condensation on the bathroom vanity mirror as well as along the upper portion of the bathroom interior wall.

From here, I also saw and felt a very fine condensation around the metal sides of our bedroom Fantastic Fan which is located in the middle of the unit and almost at its highest peak. There was also the same kind of mist-like condensate extending outward for a short distance toward the end of the unit.

I did not notice or feel any signs of leaking - stained marks, softness, drips, rusty coloured screws, etc., anywhere around the Fan, the bathroom vent, or light fixture.

As a precaution, I took the unit in for an inspection to get some further advice as to what might be causing this condensation. The service tech asked me if I had a heater on at any time and I had -- just a small, 100W home-made light bulb tin-can "heater" which I have used many times before.

According to him, this little heater was enough to cause a temperature change and when we experienced some colder weather, there was a mix of warm and cold air causing condensation. He advised not to use any kind of heat inside when in stored for the winter.

He also checked for evidence of any leaks and could not find any but we did agree to have the unit in for the day and they would clean and recaulk all of the vents, A/C, and anything that stuck up through the roof as a precautionary measure. The roof looked very good and has all been resealed.

Today, I went outside again to do another check. Guess what? Condensation (mist-like) --- in exactly the same area as before. I have had a cover on the RV and roof vents cracked open. No heat. I also have two containers of Drizair crystals placed in the unit. One on the kitchen table, another in the bedroom.

The area that is affected is in the middle of the upper bedroom - around the center fan/vent and a portion of the bathroom ( away from the exterior wall).

Will be dropping by the RV facility today to have a chat with the tech.

In the meantime, any suggestions as to what might be causing the condensation?

I am thinking wet insulation in the roof but hope not.

[curlyfungirl]

Keep us posted. I had a condensation problem a few weeks ago when the storage tanks froze up and the bathroom sink backed up. I dried everything up and haven't seen anymore condensation. That was a VERY cold few days when that happened.

[geo]

Festus2 -

I realize this would involve running an extension cord outside and all ... But we got an Eva-Dry 2000, if I remember the model correctly, and used it to keep the humidity down in the fiver. It worked very well. Before installing underbelly insulation (mentioned in previous posts) the Eva-Dry would pull about a liter per week of water out of the closed up Alpine. Once the insulation was installed, that dropped to a little less than a half-liter. Besides, I didn't have to buy the dry chemical anymore!

Ron

[hankpage]

Festus2, I can't see the dry heat from a light bulb causing condensate. But with the uniquely damp weather in your area plus the cover I guess anything is possible. Checking the roof insulation should be easy enough by removing the interior trim from the vents and reaching in with your arm but I don't think it is damp since all the caulk looked good. Keep us updated, Hank

[Festus2]

Update #1 - (hankpage) After hearing about the re-occuring condensation problem, the service tech was quite puzzled. He said that, when he recaulked/resealed the roof, he reached inside the area around the Fantastic Fan and the insulation was dry. I will do the same from the inside just to double check.

He suggested wiping off the condensate and putting on a fan to keep the air circulating and to make sure that the ceiling vents are open slightly. That has been done as I now have two fans going in the bedroom area where the condensation is taking place.

Curlyfungirl - All tanks were drained - other than some pink stuff which I dumped into each one - prior to winterizing the unit so I am positive that there was no water left in any of the tanks. Pink stuff was dumped down the bathroom sink, toilet, and shower. We did have several days of temps that were slightly below freezing but nothing extreme.

Geo - I've gone to the Eva-Dry website and checked out their various models of dehumidifers. They seem to be highly rated but one concern I have is that they may only be efficient in temperatures above 60 deg F. During our Fall and Winter, that just isn't going to happen. I've fired off an email to them asking about this. Not sure at this point if they are available in Canada. Will give them a call Monday.

[mikell]

I was going to suggest a box fan to keep the air moving put it on a timer to save a bit of money

[cjm]

I'm in the same area as you. I leave a adjustable heater/fan in mine with the heat set to the lowest setting. The fan moves the air though the whole trailer ( i make sure the bathroom door is propped open). This works very well, no condensation at all, no matter how wet it is outside. The fan and heater don't use much power, and the peace of mind is worth it.

[rjsurfer]

I hate to say it but where there is smoke there is fire.

Condensation on the inside is not good, I can't see a 100w heater effecting the dew point that much to create/eliminate condensation.

What I don't understand is the fact that you cover your camper, if that cover is watertight moisture should not be getting in from anywhere, roof, slideout and windows included. And if you're keeping water in the traps nothing should be getting in from the tanks empty or full.

I would double check the cover and if it's watertight I'm at a loss.

If there are spots in the cover that are questionable then all bets are off, you might check the TV antenna I have had mine leak down the shaft and the antenna is probably in that area where the condensation is.

Ron