winter storage and condensation?

[erich0521]

Hi, we are 1st time owners this year.  My 98 Jayco Heritage is having to stay outside during our Illinois winter this year.  Should I worry about condensation, mildew, etc. during a long time closed?  If so, have you tried anything such as "dry z air" which uses crystals to take out excess moisture?  Thanks

[tlhdoc]

I have had a PU since 1996 and have not had any problems with condensation during the winter.  Make sure the trailer is DRY before putting it away.  If you have any doubt, run a heater in if for several hours do make sure the tenting, curtains, and upholstery are completely dry.

[garym053]

I have used Dry Z Air every year. I have not had any trouble with Winter condensation.
My feeling re: Dry Z Air is that it makes YOU feel better than it ACTUALLY works. Unless you are opening the camper and dumping the water from the Dry Z Air container, then what is to stop all that collected moisture from being evaporated back up into the air inside your camper?
I think Damp Rid and all the other moisture absorbing products are in the same boat.
That said, ask me in the Spring as this is the first year that I am NOT using Dry Z Air or covering with a tarp!

[GWPeck]

I have used Dry Z Air every year. I have not had any trouble with Winter condensation.
My feeling re: Dry Z Air is that it makes YOU feel better than it ACTUALLY works. Unless you are opening the camper and dumping the water from the Dry Z Air container, then what is to stop all that collected moisture from being evaporated back up into the air inside your camper?
I think Damp Rid and all the other moisture absorbing products are in the same boat.
That said, ask me in the Spring as this is the first year that I am NOT using Dry Z Air or covering with a tarp!

--------
If I remember correctly from my high-school chemistry classes--the active ingredient in Dri-Z-Air is a very hydrophilic (water-loving) anhydrous-salt material, and once it grabs atmospheric moisture, will not let go of it.  

What liquid you see at the bottom of the container is the saturated-solution of a re-hydrated anhydrous salt, and the attraction of the mineral compound for the H2O is so strong, it will not re-evaporate without the addition of substantial heat.  

In the conditions found in a tent-trailer during winter months, there is simply not enough heat-energy available to drive moisture off that super-saturated salt solution, and the H2O should stay put.  The effect is not like creating a desert-dry environment inside the unit--it is more like it keeps the ambient moisture level inside the desiccated space low enough that mold growth cannot be supported.

I'm using Dri-Z-Air units in my (uncovered) 2006 Fleetwood Timberlake trailer this winter to keep the internal moisture level as low as possible here in the Seattle-Tacoma area, where (as you might have heard) it rains a bit.  I'll let you know how this works out.  I'm planning to check on the Dri-Z-Air units on a monthly basis, to see how much moisture they capture.  

I find myself wondering how great a contribution the RV anti-freeze I installed in drain-traps will contribute to what the Dri-Z-Air units capture.  Propylene glycol does not have the same hydrophilic action as Dri-Z-Air, so it should give-up something to the crystals while not freezing.

Just my $0.02 worth....

[mike4947]

What Peck said, says about it all. I would add I prefer a silica desiccant over the single use types made from calcium carbonate. The silica can be reused multiple times by simply heating it to drive off the moisture. the Dry-Ease types can be reused. My silica can is now right about 25 years old and still sucks up moisture (and doesn't give it up, unless heated) like new.
 
as an FYI, the pink RV antifreeze we buy is a premixed solution of apx 50% proplyene glycol and 50% water so it pays to make sure any lines you fill that the outflow is fully pink as any water raises the freezing point. There's 70% and 100% available but at an increased cost. IIRC West marine sells 100% (colored purple) for around $14 a gallon.
We found out about it being premixed in a seasonal park where we had regular house trailers connected to septic tanks. Come spring several regular house type toilets were cracked. All the ones that cracked were folks that simply poured some antifreeze in the bowl without draining the water first. It got deluted to the point that the -20/-30 degree temps frozen them solid.

[tknick]

What Peck said, says about it all. I would add I prefer a silica desiccant over the single use types made from calcium carbonate. The silica can be reused multiple times by simply heating it to drive off the moisture. the Dry-Ease types can be reused. My silica can is now right about 25 years old and still sucks up moisture (and doesn't give it up, unless heated) like new.
 

I have been meaning to post about humidity in the summer, and this post may have answered my question before I asked it.  The problem I am dealing with is humidity in the summer when running my A/C.  The temperature is cool enough (the a/c is working correctly), but because of the tent material and the lack of insulation, the humidity never seems to get to a comfortable level at night.  Will the Dry-Ease help with this, or just be a losing battle in the hot and humid summers of the South?  If it will work, where do I get it from?  Once I've used it, how do I heat it to drive off the moisture and re-use it?

thanks in advance
travis

[mike4947]

I never used mine when we camped, just for storage. As to how to reuse the silica desiccant just pop it in a warm oven and it'll dry right out. I can't type...the Calcium types can NOT be reused once saturated.

The silica desiccant can be found in craft stores in bulk (they sell it for drying flowers and such) and at a higher price in nice stainless containers in boat places like West Marine.

[tknick]

I never used mine when we camped, just for storage. As to how to reuse the silica desiccant just pop it in a warm oven and it'll dry right out. I can't type...the Calcium types can NOT be reused once saturated.

The silica desiccant can be found in craft stores in bulk (they sell it for drying flowers and such) and at a higher price in nice stainless containers in boat places like West Marine.

i apologize if these questions are  a little silly, but how do you tell when it's too wet to work, and how do you tell when it's dried enough in the oven?

travis

[chasd60]

Ever had a cold beer on a warm day? Ever noticed the condensation that forms on the cold surface of the can, bottle or glass?

When I had my 2001 Viking Legend 2480ST I noticed this happening in my camper. Specifically in the front trunk. I had left the front trunk full of the stuff we carried in there over the summer. When the nights get down into the teens or lower, the stuff in the front trunk gets very cold. When the sun rises in the morning and shines on the trunk, it is kind of like a greenhouse and the inside of the trunk gets very warm. The problem is that all of the stuff inside the trunk is still ice cold. Condensation forms on those items and can drip on the floor of the trunk or somewhere else that can cause rot or mildew.
 
The front trunk cover is typically not insulated and lends itself very well to heat gain. I learned to empty the front trunk for the winter and to open every door and panel to all of the cabinets for the winter. Moisture and humidity tend to equalize in an open space. Ever heard of people talking about rot in the floor of the trunk? I think this is what causes that.
 
Just my experience.
 
Silica dessicant now comes in pouches/bags that are of the same material as tyvek barrier used on houses. We use them a lot in the semiconductor industry when we have to dry-bag semiconductor chips that are rated at a lower than optimum moisture level. I'll check the label on the pouches/bags and get back to this thread with the temperature and time for the bake.

[chasd60]

The stuff we use comes from here
http://www.multisorb.com/applications/products/desiccants/bags/natrasorb_html
And the info on the bag says "Reactiviation Time in Bag - 16 Hrs. @ 245F"
 
Based on the info from that web site you can tell how full it is by weight.
 
You could also buy some of these Humidity Indicator Cards
http://www.multisorb.com/products/desiccants/index_html/cards/humonitor_html

[wynot]

I have been meaning to post about humidity in the summer, and this post may have answered my question before I asked it. The problem I am dealing with is humidity in the summer when running my A/C. The temperature is cool enough (the a/c is working correctly), but because of the tent material and the lack of insulation, the humidity never seems to get to a comfortable level at night. Will the Dry-Ease help with this, or just be a losing battle in the hot and humid summers of the South? If it will work, where do I get it from? Once I've used it, how do I heat it to drive off the moisture and re-use it?
 
thanks in advance
travis

Having lived (and camped) in lots of hot and heavily humid places...
 
- Cover the bunkends with solar covers.  Someone makes them custom for each model popup for all the canvassed areas.  I apologize that I can't remember who...  This will insulate the bunkends and reflect heat back.
- Run the A/C cold enough that it actually does dehumidify rather than just cool the air.
- Do NOT under any circumstances cook, shower, or wash dishes in the popup when it is hot and humid outside!!!
- Don't leave any area vented (like a door or flap) when the A/C is on.
- Don't burn the gas stove or Coleman gas lanterns inside.
- Camp in the shade if you can (I know, try finding shade under a Carolina pine...)
 
We've camped in all the hottest places in NC and SC (and throughout the MidAtlantic) with absolute 100% humidity, 90-100 deg temps, and no air moving without being uncomfortable.
 
Hope this helps!

[fshnfool76]

I put 2 of the Damp Rid containers in my pup last winter. It was a first time for me, they were about the size of a quart of paint. I put one toward the front and one toward the back. They went in around the end of Nov. and came out around the end of April. Each one only had about a 1/2" of liquid in them. I was expecting alot more since we had a fairly wet winter here on Long Island last winter.  Hope this helps!

[GWPeck]

UDATE:  Dri-Z-Air crytals in my 2006 Fleetwood Timberlake...I placed two Dri-Z-Air units in this rig in mid-September, 2006 with the intention of checking on their effectiveness every month, and making a report.  It did not go that way, but I did get a chance to check today, and the results were very positive.

We live in the Tacoma, WA area, where we had over 24" of rainfall in November-December, plus a 100+ mph windstorm and snow/ice/freezing temperatures right afterwards.  My PU sits uncovered in a RV storage facility, wind-sheltered from the north-south weather we usually get.

The Dri-Z-Air units were not quite exhausted when I pulled the canisters this afternoon--there were still crystals in the top of one of the units, doing their job.  This was approximately 5 months duration.  I re-freshened the "fill" in both canisters, and put them back to work.

We'll still have to get the tent opened-up and well-inspected to see if everything is A-OK---but, I'm gratified to know these little chemical goodies were working all this time.  Outside temperature changes alone are enough to move moist air in and out of a PU when its is packed-up and parked, so it is comforting to see the Dri-Z-Air working on that.