Maxxair fan location advice please!

thejm · 05-13-2020, 04:02 PM

Finally about ready to cut a hole in the roof of my E-350 RB! Before I reach the point of no return, I'd love some opinions on placement of the fan. There are two spots I'm leaning on as shown in my very fancy artist renderings.

A: I'm liking the spot closer towards the middle of the van as I will be putting a little kitchenette in the typical spot behind the driver's seat and will be cooking/boiling water often during the winter. Will wind noise be an issue in this spot as it is closer towards the front?

B: The rear spot is more centered over where my bed is. This has the advantage of cooling down on the hot nights...which will likely be far and few between as I typically spend the hotter months trying to escape the heat of Los Angeles! Perhaps less wind noise in this area?

My priorities are:

1. Avoiding wind noise.

2. Avoiding condensation while boiling water during the winter.

3. Sucking out the heat during the summer.

4. Putting the fan in a place I'll later regret!

All opinions welcome. Thanks!

CGgonzo12 · 05-13-2020, 05:29 PM

I too am curious about this exact question.... I will be watching

Steve Hunt · 05-13-2020, 06:42 PM

My van is in process so I don't have any first hand experience yet but in industrial ventilation you can't talk about the exhaust location without talking about the intake location. Maybe that helps you decide. Generally speaking intake is on one end of the area and exhaust on the other, this will clear the area the best. So do you plan to crack the front windows or the rear?

thejm · 05-14-2020, 01:12 AM

Hey Steve, hadn’t really thought of that. I usually keep the front windows cracked. I have rear pop out windows that will be going in sometime soon. If it was in the middle does that mean I can choose to open either front or back to get the same effect?

1der · 05-14-2020, 07:56 AM

The comments re ventilation flow are right on. Also, it is nice if the fan you have is reversible so it can bring air in from the top as well as exhaust air out the top. If it is only exhaust, that is fine. Having the rear pop outs (add screens to those) and front window vent visors gives you some options to work with. The ability to have windows that can be open the rain is very important.

What most people fail to consider when installing a roof fan is the placement of solar panels and/or other roof mounted accessories - ski racks, boxes, etc.. An inch or two can make a major difference on panel placement. And then there is the shading factor when the vent lid is raised. The lids raise up quite a bit so having a solar panel in close proximity to the fan will greatly impact solar output if the lid shades any portion of the panel.

You mention boiling water which certainly introduces moisture. There is also the moisture from wet/damp clothing and gear. And there is a bunch of moisture that we exhale just being alive. Just while sleeping it is nearly two cups of water per person. Just imagine two cups of water placed on the counter and that amount evaporating into your interior. While moving around exhaled and perspiration moisture is emitted at a higher rate than when sleeping. Hard cold surfaces like windows and exposed interior body metal will collect lots of moisture (it will be frost if it is freezing outside). So, running your fan will help with reducing the moisture inside. Hope that helps!

Kibo · 05-14-2020, 07:58 AM

I have my MaxxAir approximately where you have the letter 'A' (the letter itself, not where you drew the fan). I've found the popping the rear windows and sucking air in works best for cooling the van, as you get a nice draft lengthwise. For your particular setup with the bed in back I think this would be best, as the air will be drawn through the pop-outs and across your bed. If you put the fan near the back, it will be louder and you won't get a cross draft.

Opening the front windows and/or the side pop-outs shorts the air path, and the van doesn't cool down as much, but it can be nice to open the passenger side window and sit in the swivel chair as the air is drawn across the seat.

No issues with wind noise in this location that I can tell, but I also have a mid/high pop top. I also don't cook inside the van and can't speak for that.

Steve Hunt · 05-14-2020, 08:14 AM

Quote:

Originally Posted by thejm

Hey Steve, hadn’t really thought of that. I usually keep the front windows cracked. I have rear pop out windows that will be going in sometime soon. If it was in the middle does that mean I can choose to open either front or back to get the same effect?

Well that's good as it gives you more options. I'm guessing opening or closing front or rear windows won't won't be a hassle much when camping. So yes play with openings front and rear if you go center mount fan but for heat evacuation it will be way more convenient (not to deal with the pop-outs) and to crack the front window when you park and let the rearward mounted fan pull hot air out. I live in FL so a vehicle baking on a black top parking during the day even for just a hour gets insanely hot. I think some or all of the Maxxair have a remote control and auto on thermostat. The cargo area is a huge volume to cool as it is without starting with a 140 degree oven.

Steve Hunt · 05-14-2020, 08:21 AM

This is a good thread for me too since my fan is not mounted yet either and i hadn't thought about a couple of the other's comments so far.

**BroncoHauler** · 05-14-2020, 08:45 AM

One other consideration is the amount of light coming through the cover if it's near the head of your bed.

Herb

AndrewInSeattle · 05-14-2020, 08:56 AM

We have 2, one near the front and one near the back, so it's great being able to reverse one and create a ventilation loop without necessarily opening any windows.

We do cook in the van occasionally, so having the fan almost directly over the countertop is useful to avoid having steam and odors getting into other parts of the van. Speaking of odors, do you plan to have a toilet in the van? Also useful having a fan as close to that as possible to expel air without spreading it towards anyone else in the van.

The lid on our front fan does rattle just a bit at high speeds (interstate plus headwind), which I'm not happy about. I occasionally get up to hand-tighten the crank to minimize it.