Active Approach to RTT Mattress Condensation Issues

[mmaattppoo]

After three years of adventures with my Tepui Kukenam tent I've finally added two 2" 12 volt fans to pull air through the ventilated floor tiles I've been using to keep my mattress off the floor and out of the condensation that builds up.

The intention here isn't to have a hurricane under the mattress. Instead the 20-30 CFM of air moved by the fans (active portion of the system) will gently flow air under the mattress to evacuate moisture laden air while sleeping and for a couple of hours after waking up in the morning.

Power for these fans will be run from inside the tent from the outlets powered by house battery installed in the back of my JKU Wrangler.

Here are a few photos of the installation and a couple of images exported from SketchUp of what the installation looks like when the tiles are in place...no photos of the tiles installed when I tried them out over the Labour Day long weekend.

The fans with protective wire screens.

The first cut and stryrofoam insulation sandwiched between the inner/outer aluminum floor panels.

Holes cut.

Fans installed.

Close up of installed fans.

Wiring loomed and secured.

SketchUp image of where the fans are installed.

SketchUp image of how the ventilated floor tiles are placed under the mattress.

Still have to solder a plug on the end of the wires from the fans and then test out the system.

Sent from my SM-N920W8 using Tapatalk

 

[MagicMtnDan]

So is there another set of 2 holes in the exterior of the panel for the fans to bring air in?

Is the idea to have the ventilated floor tiles disperse the air flow throughout the tile area?

 

[mmaattppoo]

So is there another set of 2 holes in the exterior of the panel for the fans to bring air in?

Is the idea to have the ventilated floor tiles disperse the air flow throughout the tile area?

No additional holes. The fans will pull moisture laden air from beneath the mattress and blow it out of the tent through the floor. The tiled area will be bound on the sides by strips of HPDE plastic (approximately 1/4" thick and similar to the thickness of the tiles) to restrict the inflow of air from the sides. The mattress will act to further limit the inflow of air to the open ends.

We usually leave the front entrance and rear window open slightly. Hopefully exterior air drawn into the tent and under the mattress will contain less humidity than the air that would otherwise stagnate under the mattress overnight while sleeping.

Here's a markup of the second SketchUp image that attempts to clarify how air is intended to enter, flow through, and exhaust from the tiled area.

It might be a while but I'll post a few photos of the completed installation to more clearly illustrate how the parts fit together. The SketchUp images are quite small and don't clearly show the individual pieces.

Sent from my SM-N920W8 using Tapatalk

 

[jeffv2718]

Interested in this for mine. Which floor tiles are you using to keep the mattress elevated? Any issue folding up the tent with those installed? I'm currently running with a foam mattress topper over my original mattress so I'm concerned about folded thickness as it is. Thanks!


Sent from my iPhone using Tapatalk

 

[SnoViking]

That's an awesome idea! I'm curious how chilly it would get on cool nights. Although it might keep things cool on hot nights also.

Did you hook the fans up to a rheostat?

 

[mmaattppoo]

Interested in this for mine. Which floor tiles are you using to keep the mattress elevated? Any issue folding up the tent with those installed? I'm currently running with a foam mattress topper over my original mattress so I'm concerned about folded thickness as it is. Thanks!


Sent from my iPhone using Tapatalk

I'm using a product called Multy Tiles available at Home Depot (https://www.homedepot.ca/en/home/p.multy-tile-kit-10-pack.1000141852.html).

Here's a photo of one of the tiles:

The tiles are approximately 1/3" thick so they don't add much thickness when folded up.

The small air gap formed between the mattress and tent floor is ample to prevent the mattress from coming into contact with condensation and should allow for sufficient air flow with the fans (20-30 CFM) to prevent (or at least reduce) the amount of condensation that builds up overnight.

I ran with these tiles installed as an experiment over the Labour Day long weekend (without the fans) and they worked quite well. The mattress was kept dry and condensation collected on the floor of the tent which was easily wiped up with an absorbent microfibre cloth.

Sent from my SM-N920W8 using Tapatalk

 

[mmaattppoo]

That's an awesome idea! I'm curious how chilly it would get on cool nights. Although it might keep things cool on hot nights also.

Did you hook the fans up to a rheostat?

Thanks SnoViking. This is a project that's been sitting on the bench for months and I'm glad I finally got the fans installed.

I don't think the two fans will really do much to affect the temperature inside the tent as together they only move 20-30 CFM (max). The amount I keep the screened windows open to allow replacement air in probably affects temperatures more than the fans would on their own. I'll need to complete the installation of the ventilation tiles and then spend a few nights in the tent with the fans running and monitor interior temperatures.

At this point the fans are wired in parallel and will be wired to existing 12V power in the tent from my house battery/solar panel system. I'll be using a SPST switch to turn them on and off. Given that the fans each draw only 0.14 amps (~0.28 amps combined) a simple switch should suffice for controlling them for now.

Down the road I may add a speed controller of some sort (e.g. a $10 PWM speed controller off of Amazon or eBay) to control these small brushless motors as it would be nice to experiment with how fan speed affects the effectiveness of this anti-condensation buildup concept.



Sent from my SM-N920W8 using Tapatalk

 

[Riptide]

Probably too far into your project for this, but boaters deal with this even more than campers do. We have a Froli sleep system under our mattress in our Westy Sprinter, and besides eliminating condensation, they are available in different spring rates, so you get a pretty comfortable mattress too...

http://www.frolisleepsystems.com

 

[mmaattppoo]

Probably too far into your project for this, but boaters deal with this even more than campers do. We have a Froli sleep system under our mattress in our Westy Sprinter, and besides eliminating condensation, they are available in different spring rates, so you get a pretty comfortable mattress too...

http://www.frolisleepsystems.com

Indeed. Thank you for the suggestion. Froli's sleep systems were tempting and something I had seriously considered but the cost of the Travel model ($189 USD) was somewhat prohibitive. Addituonally, the overall thickness of the tent when folded steered me on my current course. According to Froli's website the sprung height of the Froli Travel is 1 3/8" (doubled to 2 3/4") when folded would likely eat into the ability of leaving bedding inside the tent with the mattress when travelling between sites.

Between the fans, wiring, and Multy Tiles I'm into this project for about $60.

A long term plan is to buy a sailboat. Froli's products will be in the running when the time comes...some day.

Sent from my SM-N920W8 using Tapatalk