Energy Recovery Ventilation in Vans

Hi folks! I am wondering about the issue of ventilation in the van. There are of course simple fans that extract the air. However, extracting heated or air conditioned air equals energy loss. What to do? I know about energy recovery ventilation. Has anyone tried an energy recovery ventilator in a van?

Greetings & Welcome!

With all due respect, what’s possible, isn’t always practical. Having a little extra heating or cooling is simpler, and doesn’t add any extra components to break down or malfunction.

Over the years, I’ve tried a lot of more complicated and/or more expensive solutions to simple problems. In the end, my original solution always turned out to be the best.

Climate control is one of the easiest challenges we face. I’ve done winters down to - 60°f and summers up to 120°f and high humidity too. With a wick type kerosene/diesel heater that requires no power, & an indirect style swamp cooler, I can be comfortable inside my rig 24/7. Since the heat requires no power, and the swamp cooler only draws 1.9 amps @12v on high, and under 1 amp on low which is where it is usually set, it is very energy efficient, and can flat freeze you out.

I have a high top van with windows all the way around, that I rarely cover, and no added insulation, heating & cooling is simple & easy. Sun in the winter, shade in the summer, and additional heating or cooling if needed.

Adequate ventilation is required at all times to prevent moisture build up. Since ventilation alone is used much more often than either heating or cooling, keeping it as simple as posssible has obvious advanntages.


KISS (Keep It Stupidly Simple). The best solution to Murphy's Law." ~ Van_Dweller

Thanks so much for your insights:) I was looking at energy recovery ventilators. All it has is two simple fans and an enthalpy exchanger that does not consume any energy. So, it looks like it would be somewhat bigger than a fan and consumer only a bit more energy than a regular powered fan. It allows not just heat but also moisture to move between the incoming airstream and the outgoing airstream. So, it would also help with moisture control. Have you every tried something like this anywhere at all - even in your home?


Yes, I tried one, and the only notable difference was it’s huge energy consumption. Each of it’s fans drrew about 1 amp, so 2 fans x 24h =48 amps per day, with no notable improvement in heat required, or moisturre reduction.

Cutting out the bulkhead so air could circulate front to back, and switching away from a Mr. Buddy heater to a dry, wick type kerosene heater was what actually solved my problems. (The 2x expensive roof vents didn’t help either.) The dry heat & removing the bulkhead were the winning strategies. After that I added those pillow type roof vent insulators to the roof vents, and that made a huge difference in the amount of heat I needed to stay comfortable. No more ice in the cab either.

Dry heat and a fan to circulate that heat all around rather than just at the ceiling seems to work the best.


KISS (Keep It Stupidly Simple). The best solution to Murphy's Law." ~ Van_Dweller

I’ve done winters down to -120°f and summers up to 120°f and high humidity too.

A lot of what you say seems made up, but could potentially be true. However, claiming that you have been perfectly comfortable in an uninsulated van at -120F is total BS. There’s only been a handful of occasions where the temperature has even gotten that low in the last 100 years, and they were all in Antarctica.

As another aside, swamp coolers do not work in high humidity.

Climate control in a van is an easy challenge only in two situations: You either live somewhere like Hawaii where the climate is extremely amenable, or you exaggerate and fabricate stories.

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GOOD CALL! That was a typo, and I missed it. (Corrected now…) It should have said -60°f. I have spent many winters in Northern MN, & MI, the Dakota’s, WY, & MT, as well as Alaska.

There are multiple kinds of swamp coolers, and there most certainly are types that work marvelously in high humidity areas, and they’ve been around since I was a kid, and there are some in Southern mansions dating back to the mid or early 1800’s that are still in operation and still working perfectly today, and in very high humidity areas.

You are correct that the direct type doesn’t work as EXPECTED in high humidity areas, but the indirect type works perfectly, and will actually dehumidify the air. It uses a heat exchanger much like an air conditioner, and the moist air is exhausted back outside. Mine is the indirect type, but that being said, even the direct type can be effective in high humidity areas if used correctly, and while they won’t dehumidify the air, they won’t add moisture either because any added moisture will be exhausted out the other end of the house or vehicle through an open window, door, or vent.

The problems people have with swamp coolers are usually self inflicted. Like a window air conditioner, swamp coolers are meant to be mounted in a window, or placed directly in front of one. If they’re not, they simply won’t work correctly. A portable AC won’t work if it isn’t ducted to the outside either. Exact same principle.

Some AC’s have the option of fresh air or recirculated air. That is the same difference between a direct & an indirect swamp cooler, the latter being the recirculate mode. On fresh, an AC will work better with a window open on the opposite end, same with a direct swamp cooler. On recirculate, you keep the room closed up, same as with an indirect swamp cooler, but all types should be mounted in a window to work properly.

While a window mounted indirect swamp cooler will dehumidify the interior, and the direct type does not, it will only add moisture to the air if it has nowhere to exhaust it. With a proper exhaust, the indoor & outdoor humidity will remain the same.

As a nomad, power consumption is important, but if we choose wisely, there are solutions to every problem most of us will ever encounter.

If you study up on it, you’ll find that most, if not all forms of refrigeration and air conditioning are based on evaporative cooling, and that there are just different ways of getting from point A to point B. The only advantage that compressor AC’s have over swamp coolers is that you don’t need to add water, but that convenience comes at the expense of needing much more electricity and nasty refrigerants.

Climate control in a van or RV is easy if you choose the right options. I’ve spent the last 4 summers south of Miami, fairly hot, & very humid, quite comfortably. Three of those were with a swamp cooler, and this last summer was with a closed loop system that uses thermo-electric to heat/cool the coolant running through the heat exchanger. It worked well for the summer, although it didn’t dehumidify as much as my swamp cooler does. The jury’s still out for how well it will work over the winter back up here in Minneapolis & Duluth. I do still have my original equipment in case I need it.


"Never gamble more than you can afford to lose." ~ Dare2Dream

Wow - this is so useful! Thank you!

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You seem to know a lot about this via trial and error I commend you. I know you are explaining how you have this set up in an RV, but would you think it possible to do this in a minivan? I don’t see where a hole would go that the water drips out. And kerosene must need a fan for oxygen circulation just as butane does? A Minivan doesn’t have the ways of fitting a window mounted anything as you lucky RV’s have. I guess it’s not likely to do in a mini van without tearing it apart. Im basically looking for a way to reduce humidity and temperature in my minivan, because of sensitive electronics and hard drives. Thanks for any advice.