Being in a hot campervan sucks.
We’ve spent more than 18 months living in our campervan, touring through some of the hottest and coldest climates Europe and North America have to offer.
And by far the worst experience we've had has been in hot, humid conditions where it’s so uncomfortable trying to sleep.
There are endless options out there for RV air conditioners, but we chose to research the different 12v air conditioning units out there.
And one caught our eye … the Zero Breeze mark ii portable air conditioner!
Typically designed for camping, we decided it could be the perfect solution for our camper.
So we reached out to the company and offered to do an in depth review of the Zero Breeze mark ii.
Looking specifically at how well it can cool a larger space, and also how efficient it really is.
But here’s the really exciting part …
We decided to hard-install it into our campervan conversion, wiring it directly into our large on-board 12v camper batteries, to see if it can be a viable long-term van-life solution.
Below is our review based on more than 2 years of fulltime use!
Here’s what we found …
Zero Breeze is a new company founded based on a love for the outdoors.
Back in 2014, Max, the company’s founder noticed that suitable outdoor air conditioning simply didn’t exist, despite there being an obvious need for one!
After being disappointed by other products over the years, he started Zero Breeze, and they went ahead and created the first real portable battery-powered air-conditioner- the Zero Breeze Mark 1.
Today, they’ve launched a more fine-tuned product, the Zero Breeze Mark 2.
The Zero Breeze Mark 2 is a 100% portable, battery-powered AC unit that allows people to experience more comfortable with outdoor enjoyment; while also making life more comfortable for outdoor workers and special patients who physically can’t endure the heat of the outdoors.
2023 update** Zero Breeze have also launched a portable power station. The perfect accompaniment to their AC unit. Read more in our review of the Zero Breze ElecHive portable power station.
The Zero Breeze air-conditioner functions in a similar way to other portable air-conditioners out there.
But what sets it apart is it is 100% battery powered.
Which, just so you know, is a VERY big deal for an air conditioner; a device that would typically draw an incredibly large amount of power.
There are three main mechanical cooling components jam-packed into this compact AC unit: a compressor, condenser coil, and evaporator coil.
Those are in addition to the special cooling agent the machine uses known as refrigerant.
First, the Zero Breeze draws warm air into the unit through the front of the unit, using its centrifugal fan.
Then, the hot air flows over the evaporator coils, and the refrigerant in the machine absorbs the hot air.
The hot air causes the refrigerant to change from a liquid to a gas, which creates cooled air.
During the process of condensing the liquid to a gas, hot air is created. All of that hot air is evacuated to the outdoors through the help of the condenser coils, and a second fan in the machine.
Essentially, the Zero Breeze sucks in warm air using a fan, and its inner mechanisms create cool air to be released back into your campervan, while venting out the hot air.
Okay, now that we’ve got all the technical mumbo jumbo out the way, let’s dig into how you actually use it!
In an open space, using the Zero Breeze Mark 2 is as simple as having cooled air at the press of a button.
It will then direct a jet of cold air through the front funnel, and you can sit directly in front of it in order to feel the benefit.
Of course, the other big way to use the Zero Breeze is to cool an enclosed space; such as a tent or camper.
However, when using the Zero Breeze in an enclosed space like a campervan, you’ll need to make sure that the two rear ducts are pointing outside your van with a tight seal that allows no air to come in or out from outside, except via Zero Breeze!
Otherwise, you are going to be fighting a losing battle, as the warm/hot air from outside will constantly be seeping into the space you are trying to cool.
The Zero Breeze also produces slight condensation, so you'll have to be sure the condensation tube drips to a proper area either in or outside of your van upon installation.
Once your Zero Breeze is set up inside your van with the rear ducts properly venting to the outdoors, you're all set for an air-conditioned van!
Quick answer: Yes it does!
The basic function of the Zero Breeze is 2-fold:
And yes it does both of these things extremely well.
But there is one really crucial thing I want to point out here …
The Zero Breeze will never compete with typical household/240v campervan AC systems. It just isn’t possible in such a small unit.
I’ve read a bunch of Zero Breeze reviews where people claim it doesn’t do what it claims or it isn’t able to cool their giant campervan.
And that’s because it’s not meant to.
It is designed to be a portable cooling system, great for making smaller spaces comfortable.
And it does that really well.
Especially as the battery life extends to up to 6 hours at a time (in night-time mode).
Before hard-installing our unit, we tried it in Greece, just having the tubes coming out the window (sealed using the provided foam) and no it was not able to drastically cool the van.
The unit was pumping out really cold air, and it was comfortable so long as you sat in front of it.
That’s when we realized something important:
The Zero Breeze is never going to keep a large space cold, especially when parked in sunlight where it’s being heated.
At the same time, if you left it on for hours on end, it would drain a LOT of power.
Instead, we realized the best way we could use it in the campervan would be for night time use.
During the daytime, we’re usually out exploring anyway, or driving in the van where the onboard AC keeps us plenty cool.
Instead, the best use for Zero Breeze would be at nights, when we’re in places where temperatures don’t drop very low at night time and it’s incredibly humid and uncomfortable to sleep in.
And for this purpose it works perfectly!
We actually hard installed the Zero Breeze into our onboard 300ah 12v Lithium Ion polymer battery.
The battery bank that the Zero Breeze comes with is a 24v battery, so it did require some technical jiggery (more on that below)
But what this means is, instead of lasting around 5 hours (as per the Zero Breeze battery’s capability) we can leave it running all night long and only use around 80ah (see below for full rundown of power draw).
Our Roamer leisure battery comes with an awesome app which lets us see exactly how much power is left and also being used at any one time.
Which is fine as, in conditions where you need it on, these are very sunny. And our solar panels + alternator charger are more than enough to then recharge the batteries during the daytime.
On the flipside, if we only used the supplied 24v battery pack, it would prove much more difficult trying to remove and recharge every day.
So, what’s the bottom line here?
For a unit that only draws 80ah, the Zero Breeze is absolutely amazing!
It can be seen as expensive, though I honestly do believe it's one of the best campervan accessories out there, and more than worth the money.
But only so long as you use it correctly and don’t expect crazy results from it.
Having it hard-installed like we do is really useful as there is no real maintenance or adjustment needed, and we know we always have a perfectly sealed space fr it to function, without needing to mess around with awkward tubes.
It has become literally a life saver since we had it, and use it almost every day without fail when in hot humid countries over 2 years!
We actually picked up an additional extender piece of tube from a Canadian Tire store in Canada.
Though it looks a little gangly, it's super convenient as we can perfectly direct airflow to any part of the van where we need it.
BONUS TIP: If you are going to hard install into your campervan, then you don’t need to buy a battery bank, saving you around $500 off the purchase price.
BONUS TIP 2: Zero Breeze have now launched a portable power station called the ElecHive 2500 (read more in our review here). It is a great addition and could be better than buying additional AC batteries.
The best place to buy a Zero Breeze (and only place as far as I am aware) is direct from their website.
No, they do not yet seem to sell on Amazon.
You have the option of picking up the unit itself, as well as any additional parts you may want.
From firsthand experience, they do have a really cool customer support team there, and getting any support you need shouldn't be too tricky.
They did answer any questions/concerns I had during this rather strange install process and I’m chuffed with how it turned out.
As well as buying spare parts in case you break something, you can also buy some additional cool products (I wish many of these were available when we built ours into our camper!).
Additional accessories for Zero Breeze mark 2:
To help make this post a little more technically useful, I did a live run to see how much power the Zero Breeze draws on different settings.
Note: The exact numbers will vary depending on:
So for our camper's 12v lithium ion battery, at the time of the test, here is how much background power draw there was:
As you can see it's at around 4.5 amps (higher than usual, and I believe it was because the fridge was working harder to cool at that moment). Other than this, no other appliances were on.
This was taken after a few minutes of allowing the unit to run and the power fluctuation stabilised at around 15 amps.
Minus the 4.5 background amps, this means the Zero Breeze on standard setting was drawing around 10.5 amps.
Averaged out over a night time of 10 hours, you could assume it would drain about 105 amps.
Next I turned it up to Boost mode, which is the full power setting to provide maximum cooling.
As you can see, the power draw seemed to stabilise at around 17 amps. So again, taking away the background draw, it was using around 12.5 amps an hour on this setting.
So left like this overnight for 10 hours, it would draw 125 amps. Not bad really, for the sake of 25 extra amps, in somewhere really hot and with our super large power bank, I would be happy to leave that on.
The purpose behind this is to reduce power drain to allow the unit to last overnight with the provided power bank.
As you can see, for us this dropped the overall draw down to around 12 amps. So 7.5 minus the background draw.
So left on for 10 hours, this would draw 75 amps. Quite a lot less than the boost mode, so definitely a useful setting as the cool air pumped out is still reasonable.
For the purpose of fairness, this just shows the draw of the batteries once I switched the Zero Breeze off again. As you can see, the draw is still around 4.5amps, meaning at this time the fridge was still drawing more power.
Coming in at around $1,500, many people will find the Zero Breeze to be relatively expensive.
Indeed, it may not be necessary. For the first year of van life, we had nothing more than our trusty Maxxair MAXXFAN, a staple in the van build world.
This is a great, low energy fan which, coupled with a vent at the other end of your van, enables you to draw cooler air through the van, cooling you this way.
We still use this, and it really is great, up until a certain temperature.
But in terms of price point and power draw, it really is very effective, below is the power drain without the MAXXFAN on:
As you can see, it's around 0.8 amps (less than at our previous test with the Zero Breeze, and because the fridge was no longer working as hard to cool).
And below is how much power the MAXXFAN draws when switched on at a setting of 60% power, air out:
At a little over 2 amps, this means the draw is about 1.2 amps an hour ... AN HOUR!
Meaning that it will pull only around 12 amps, if left on overnight for, say 10 hours.
Which puts it at around 10% of the draw of the Zero Breeze left in on standard setting.
It also costs about $1,000 less.
Of course, it cannot provide anywhere NEAR the cooling capability, but unless you plan on going into truly hot, humid places, it will definitely do a great job of keeping you cool; and I can highly recommend it.
Bottom Line: Knowing that I have both the MAXXFAN AND the Zero Breeze, means we know we will always sleep cool at night!
We do a lot of awesome road trips, may of them to really hot, humid countries.
And having some form of 12v air conditioning always seemed to us to be some kind of wild fantasy ...
But now it isn't!
With some creativity, it's possible to build the Zero Breeze Mark 2 air conditioner into your van and have an easy, convenient way to get cool air at any time of the day.
But first off, it's worth noting that the Zero Breeze mark II wasn’t originally designed to be hard-installed.
Meaning, it’s designed to be used and powered by either the supplied 24v battery pack, or by plugging directly into a mains power source (110v-240v).
So when installing into our onboard 12v battery system, we had to get a little bit creative.
At the point we did our install, there was no video online where anyone had done what we had in mind.
There were some useful videos, namely this one here, where the guy attached his Zero Breeze to his portable power station. (If you are interested in this approach, read our review of Jackery's solar generators, ads they are awesome!).
And that video is really useful, I 100% recommend watching it, as he clearly has a vastly superior understanding of technology/wiring than what I do.
But in case you are in the UK or elsewhere and can’t wait for shipping (like us) here’s the one we bought.
We decided to use his approach and take it one step further by also cutting holes in the side of our van, picking up some suitable vents (these ones here) and then fixing the unit permanently in position.
Here’s the basic process we used to install:
You can now purchase a 12v to 24v step up converter direct from Zero Breeze.
As well as a few adaptors to directly attach your Zero Breeze into a portable power station. Check these adaptors out here.
As our van conversion was done a couple years ago, we had limited space for where to install the unit, so had to be creative.
Namely, in finding a spot that had:
We had only one practical spot, and it ended up pretty good! I would do it slightly differently if we were doing the conversion from the start, but at this point we had to work it in somewhere.
If you are still planning your conversion, then you have more flexibility.
Here is everything we used to hard-install the unit in our van (you will have to find a local equivalent depending on which country you are from).
To do this you need to go ahead and get everything into the final position and give it a test run.
You are about to cut two holes in the outside of your van, so double (and triple) check everything functions correctly in that position.
We then used a metal hole saw to cut the correct size holes in the outside of the van.
Then it’s a case of feeding the plastic ducting through slightly and attaching to the fan grill vents.
You need to then screw these vents into position, after first applying a boat load of sealant to the inside so that, when sandwiched, it forms a perfect water tight seal.
As a bonus step, I also added sealant around the outer edge of the grilles, just to ensure no water is going to get in and slowly rust the metal over time.
To help with this as well, you can file down the rough edges of the cuts you make and apply some sort of rust proof protection paint.
My dad's ever so creative and graceful idea for this step was to rip the 24v battery out of the plastic housing, screw it down into the van, then screw the plastic top back on and clip the Zero Breeze back into this.
Effectively, the portable battery bank (minus the actual battery) becomes the base to pin it down.
I mean, it works perfectly, but is a very wasteful use of a $500 battery haha. I’m sure you can come up with another idea for this stage.
Either way, you just want to make sure the unit is secured properly down and can't move while driving.
You then attach the ducting to the back of the unit, which should all be lined up by your careful planning in step 1.
Unless you are using your Zero Breeze in a location with zero humidity, it will naturally produce condensation during the air cooling process.
And this water build up drains out of the back of the unit. So you need to ensure the supplied drainage tube goes downwards into a suitable place.
This could be straight out the underside of the van.
Or, for us there was no way for this to work, so we actually cut a hole in the side of our shower, and run the tube diagonally downwards and into the shower.
If, like us, your batteries are 12v, then you will need a step up converter which converts the supplied 12v power into 24v power. Otherwise the Zero Breeze won’t work.
Full disclosure, we have a van electrician who did all technical parts of our van’s camper electric install, including this.
So for a proper idea of what is involved here, you can watch the YouTube video I linked to earlier (this one here).
It does a much better job of explaining how this works, but the approach our electrician took was the same as in the video.
Alternatively, you could just buy the converter directly from Zero Breeze and save yourself a lot of faffing around.
One thing we discovered was that, once it’s wired in, there is a red light that constantly remains on, on the top of the Zero Breeze unit.
It would draw minimal power over time, but as it is going to be sat for months when not in use, we didn't want the unit effectively in standby for this whole time.
So our electrician also installed a small cut off switch.
As we installed our unit 18 months after our actual van was first built, we had to be a lot more creative in how we installed the unit.
I’m actually really pleased with how it turned out, but there was definitely some creativity needed in finding the solution we ended up with.
If I was installing the unit as a part of the initial conversion, I would have 100% done things a bit different.
We know there are a few other portable air conditioners on the market when it comes to campervans. Here are a few of Zero Breeze’s main competitors, and how Zero Breeze stacks up against them:
1. Nomadic 3000
The Nomadic 3000 is a rooftop, compressor air-conditioning unit. It runs on 12V DC, meaning it can be plugged into your van’s leisure battery.
The Zero Breeze works similarly, in that it is also cools using compression.
The Zero Breeze differs from the Nomadic 3000 in that it is a portable AC unit with its own battery, and works without being wired to your campervans leisure battery (although that’s still an option).
The Nomadic 3000 is a very high-end air-conditioning unit, but it is much more expensive than the Zero Breeze.
2. Dometic Penguin II
The Dometic Penguin II is another rooftop compressor air conditioner.
However, the Dometic Penguin runs on 115AC, meaning it needs to either be plugged into an inverter, or shore power in order to cool your campervan.
While it’s at a similar price point to the Zero Breeze, its big power draw is likely to drain your campervans leisure battery, making the Zero Breeze a much better AC option for those looking to get off-grid.
3. The Honeywell MN12CESBB
The Honeywell is the only other portable AC unit on this list. It’s less expensive and much more powerful than the Zero Breeze.
However, it is quite heavy compared to the Zero Breeze, and is only suitable to run off shore power.
So again, it’s not a direct competitor in a sense.
4. Fresair Air Conditioner
The Fresair Air Conditioner is a swamp cooler, and is powered by water and 12V DC.
Its low electricity usage makes it an eco-friendly cooling option.
However, due to the nature of swamp coolers, it can only be used in completely dry environments. This is a pretty big limitation, and seeing as it is more expensive than the Zero Breeze, we prefer the latter.
After looking over the top competitors for campervan AC units, the Zero Breeze seems to be pretty unique.
A totally portable cooling unit didn’t really exist before the Zero Breeze, and we also like how you don’t have to cut big holes in your campervan (like with rooftop air-conditioners) to use it!
If you do have any questions about my review of the Zero Breeze.
Including steps you think I missed, or how the unit proceeds to perform over time, just drop a comment below!
I will happily add to the post over time and keep it updated in case it decides to pack in one day.
Hopefully not, we have some very hot countries coming up …
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