My plan for Stealth Van Ventilation.

[One Awesome Inch]

Okay here is my plan for stealth van ventilation. The point of this is to eliminate the need for exterior venting on the van. In my view, ventilation panels are a dead give away that someone may be living in the van. They make it look more like an RV and less like a work van. Living in the PNW I will need to remove humidity out of the van. Also, since I will be using the Wave 3 propane heater, which will add 2 ounces of water vapor to the air running at 1600BTUs, proper ventilation is even more important.

Let me know your thoughts on this....

1. Cut a space behind the rear license plate about 5 x 8 inches. This will be the fresh air intake. I will be adding some sort of sliding door to adjust the amount of air coming in, but my guess is that it will be mostly wide open.

2. Cut a hole in the partition wall, separating the house area from the driver area, and put in a computer fan to suck out the air into the driver area. Ideally I would like the fan to be behind the driver seat for maximum stealth, but I also want it to be above my stove to suck out any steam from boiling water, cooking etc. This fan will be connected to a 12v dimmer switch so that I can adjust the fan speed. I want it pretty low so that I can conserve battery power. Also I want the fan speed low so that I can minimize the amount heat being sucked out.

3. The air from the house area will be sucked out and exhausted into the driver area. I will open both the driver and passenger door window about 1 inch to facilitate removal of the exhaust air. I will have those window cover thingies on my doors to keep the rain out.

I wonder if opening both windows by 1 inch will be enough to prevent condensation from forming in the driver area. Thoughts?

The trickiest part of this is to figure out what speed I should run the fan at so that I can take the humidity out of the van living area, but try to minimize the amount of heat lost. However, I know heat loss is inevitable.

Any thoughts on this? Any problematic areas I missed?

 

[karl]

My concern with rear openings is when driving there is a real danger to drawing exhaust (and dust) into the van.
IF one always remembers to close the opening, and it is well sealed when closed, no problem.
My vents are computer type fans blowing out the sides, but I considered mounting them on a length of 4"dia pvc tube through the floor. In either place I have the fan activated by a switch similar to the ones that control door operated dome or courtesy lights. the fan is covered with a door using spring loaded cabinet hinges so that to operate the fan the door is opened, the fan comes on and remains on until the door is closed- sealing the vent. An easily compressed weatherstrip for the door to shut on stops drafts or back drafts. My fans exhaust toward the rear of the vehicle- that way I am always drawing air from the front, and can operate them even if the vehicle is running.

 

[GrantRobertson]

I would run the air the other direction. With the moist air going into the cabin, I'm thinking there would be a lot of condensation up there. Especially if you don't heat the front.

 

[One Awesome Inch]

I am not concerned about car exhaust entering the van via the rear license vent because the van will never be running when I am parked. Aside from not wanting to waste gas, idling is unnecessarily harmful to the environment.

I do like the idea of reversing it and having the partition fan being the intake fan and the license plate vent being the outside vent. However two things... 1. I'd prefer not to have any wiring for the fan to be in the rear door since thats also my only other door that will open. 2. If I have the air sucked thru the back, the heat from my Wave 3 will be sucked out faster since, from my current build layout, my heater is about 2ft or so from the rear. I could move the heater, but then I'd have to move the tank too as I would prefer to keep the hose and tank close-ish to the heater.

The stove and sink will be swapped around from how its pictured.

 

[flying kurbmaster]

what he means but sucking in dust or exhaust fumes is when you are driving, if you have a bad seal on a back door of a van and open a front window slightly you will notice that dust and exhaust fumes get drawn inside, from swirling wind action around the back of the truck. so if you are going to build an air intake at the back make sure you have a real good seal. Personnally I think you are overthinking this stealth thing, a standard 14x14 inch vent on the roof is pretty common on a lot of vans. I don't think it cries out someone is sleeping in me. Some work vans especially painters have a kind that swirls to draw out fumes. Another options is check out a marine store . There are some very smart, low profile vents that can be opened by unscrewing, that can either be installed on the side or roof of your van. Marine is always a bit costly but there used to be a couple of second hand marine stores in Vancouver, Popey's at the Mosquito creek marina was a good one, not sure if he is still there. If you go to MIlls supply google it they sell vents for panel trucks made of alluminium that sort of push out, fairly reasonably priced, could be fitted to the drivers side of your van, that way it would go unnoticed.

 

[flying kurbmaster]

by the way I know you don't want windows but I thinkit is going to get a bit stuffy in there in the middle of summer without a cross draught. So you might want to consider vents on both sides and the roof but all this will come a lot clearer to you as you live in it for a few seasons. What about a skylight that pops up, they are fairly low profile, I got one in my Dodge caravan and it is a game changer in the heat of summer.

 

[One Awesome Inch]

Some good points there that I will certainly consider.

That said, stealth is pretty important in my case since I will be 100% urban stealth all the time in the same neighbourhood... where my kids live and where I work.

 

[SoulRaven]

Forget about the heat loss angle, the only way around that is to have enough heat to overcome it, because the ventilation is not optional.

I'm not sure that computer fans will move enough air.

Winter is as easy as having enough heat, summer is what you need to plan for, and you need to be able to move a LOT of air, sucking it from the ceiling where the hottest air accumulates, and drawing it in as low as possible to get the coolest air.

Both can be accomplished using PVC pipe running from floor vents to near the ceiling, with inline fans. Add a return to floor T for winter usage.

 

[One Awesome Inch]

Our summers are mild here. Might get one month of temps near or slightly above 30 C. For those days I will park in underground garage. Nice and cool down there. I can rent a spot in my ex-wife's building for $50 per month thats what I'll likely be doing in the hot and really cold months.

 

[One Awesome Inch]

That is a good idea about blowing the hot air from the ceiling back onto the floor in the winter using PVC.

 

[karl]

"I'm not sure that computer fans will move enough air."

All fans are not equal- I've tried a few- these are my favorite so far http://www.amazon.com/gp/product/B000BWEIFU/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

I am using 4 in my steppy. I'd bet that two would suffice in your area in a standard van