I am always fantasizing about having a energy efficient air conditioner for van life, anyone seen any concepts in tech news or anything?

[Diysolar123]

Why would ANYBODY pump warm outside air into a car when the AC is running?! That's like driving around with open windows. That's called common sense, and your assumption makes zero sense. This thread is about air conditioning or at least cooling down a vehicle while the engine and OEM AC is off, on battery power.

My solution is obviously for the times when the car is parked while being gone, or over night. Why else would I suggest to install "window vent shades / deflectors and keep the windows cracked by 1 inch"? That's the whole idea behind this product.

You can stop telling me about your work experiences because that doesn't impress me one inch. I hold 3 college degrees, computer science (B), business administration (B) and engineering (M). I worked for Daimler Benz in Germany in Research & Development, as well as in aviation. Try again. That being said, it ends here. Not going to waste my time with somebody who tries to make a point by bringing his ego into a thread.

he does that a lot, just ignore him; the ignore feature on this forum works really well...

 

[OnTheRoadAgain]

That being said, it ends here. Not going to waste my time with somebody who tries to make a point by bringing his ego into a thread.

Yep. There are a few here who will make a point of showing you the size of their ego, rather than focus on the topic.
Just happened to me in one of my recent posts.

That said, great forum, mostly great people with a ton of knowledge and willing to help.
As my brains diminish with age, I'm fighting to make sure my ego diminishes proportionately.

 

[Hendo7]

you can buy mini splits in Mexico for less than $300 ,i had a friend pickup a 9k cool only 110v .they are GE models (not the best) but they work ,this particular one cools a 500 sq foot room in 120 degree weather just fine with only drawing less than 700 watts , i have a 5k window unit in my converted cargo trailer that pulls more watts and in hot weather i can run the ac and charge the batteries running 1400 watts of solar power ,it can be done cheaply,most of my panels are from san tan @ $45 each ,ac unit $150
3x40 amp solar controller's $180
the biggest expensive was the inverter .this all works wether the windows are cracked open or not and with out going into spec,s it just works fine ,i got through last summer with over 60 days of over 112 degree weather in southern arizona heat ,though i will be buying another 110v mini split for the trailer very soon

 

[McCarthy]

you can buy mini splits in Mexico for less than $300 ,i had a friend pickup a 9k cool only 110v .they are GE models (not the best) but they work ,this particular one cools a 500 sq foot room in 120 degree weather just fine with only drawing less than 700 watts , i have a 5k window unit in my converted cargo trailer that pulls more watts and in hot weather i can run the ac and charge the batteries running 1400 watts of solar power ,it can be done cheaply,most of my panels are from san tan @ $45 each ,ac unit $150
3x40 amp solar controller's $180
the biggest expensive was the inverter .this all works wether the windows are cracked open or not and with out going into spec,s it just works fine ,i got through last summer with over 60 days of over 112 degree weather in southern arizona heat ,though i will be buying another 110v mini split for the trailer very soon

A 9k BTU window unit pulls 13-14 amps at max, and they will run at max in that kinda weather, that's 1,680 watts. It will run a 280 Ah battery bank dry in 2 hours. In order to feed such a window unit you need a long toy hauler or a class A RV to put up 4k watt in panels and 5 x 280 Ah battery banks to make this work for over night duty, not even 24/7. One 9k BTU unit will not be enough for a large 5th wheel trailer or a A class RV, so you will be only cooling your master bed room. What do you consider "fine"? Taking the edge off from 112 F?

 

[Hendo7]

A 9k BTU window unit pulls 13-14 amps at max, and they will run at max in that kinda weather, that's 1,680 watts. It will run a 280 Ah battery bank dry in 2 hours. In order to feed such a window unit you need a long toy hauler or a class A RV to put up 4k watt in panels and 5 x 280 Ah battery banks to make this work for over night duty, not even 24/7. One 9k BTU unit will not be enough for a large 5th wheel trailer or a A class RV, so you will be only cooling your master bed room. What do you consider "fine"? Taking the edge off from 112 F?

i am running 5k window unit in a well insulated cargo trailer ,i am not a spec guy by any means i just do what works,like 2 tesla batteries plus two banks of li- po4 and you didn't mention the power being made while the solar is system is running and the fact that i live southern AZ and the 9k mini split in my house (not trailer)pulls way less amps than mentioned mentioned

 

[McCarthy]

i am running 5k window unit in a well insulated cargo trailer ,i am not a spec guy by any means i just do what works,like 2 tesla batteries plus two banks of li- po4 and you didn't mention the power being made while the solar is system is running and the fact that i live southern AZ and the 9k mini split in my house (not trailer)pulls way less amps than mentioned mentioned

In another thread you wrote just a few days ago that you have a 6k BTU window unit and 1,100 watt of solar:

i have a 6k window unit running of 1100 watts of solar panels in full sun it runs my ac full blast and charges the batteries at the same time but i do live in AZ

Now you are telling me that you have a 5k BTU window unit and 1400 watts of solar.

So what is it?!

Meanwhile you didn't tell me how much your AC takes off when its 112 F outside.

A 6k BTU window units draws about 6 A. That's 720 watts. With inverter losses etc, your 1,100 watt panel will run your AC for like 5 hours in AZ with little to spare. After that you will not last long on your batteries unless you charge them otherwise.

This thread was still about VAN LIFE. Your well insulated cargo trailer suggestion will not work on a small van. In order to put 1,100 or 1,400 watt on a van, you will need a long sprinter and most can't or don't want to afford those, and it will not be enough to bring temps down to the mid 70s, let alone 24/7.

Also, most vans are not or very badly insulated. Most have windows, and when you start adding 1" of foam and an air gap to a van you will lose a lot of valuable interior space.

At this point, there is no good off grid AC system for a VAN (minivan, passenger van, cargo van), that is 100% solar / battery powered. You simply don't have enough roof for the amount of panels needed. And a solution that works for a few hours a day is not a proper solution.

 

[McCarthy]

I think some don't understand what VAN LIFE is (topic of this thread). We are not talking RVs or trailers.

Here a few typical images of people who live in vans, many of them full time!

You can find them on most Wal Mart parking lots late at night. Those are people with limited funds, and limit roof space for solar panels, and limited room for batteries.

 

[Hendo7]

typo on the 6k i have actually

In another thread you wrote just a few days ago that you have a 6k BTU window unit and 1,100 watt of solar:



Now you are telling me that you have a 5k BTU window unit and 1400 watts of solar.

So what is it?!

Meanwhile you didn't tell me how much your AC takes off when its 112 F outside.

A 6k BTU window units draws about 6 A. That's 720 watts. With inverter losses etc, your 1,100 watt panel will run your AC for like 5 hours in AZ with little to spare. After that you will not last long on your batteries unless you charge them otherwise.

This thread was still about VAN LIFE. Your well insulated cargo trailer suggestion will not work on a small van. In order to put 1,100 or 1,400 watt on a van, you will need a long sprinter and most can't or don't want to afford those, and it will not be enough to bring temps down to the mid 70s, let alone 24/7.

Also, most vans are not or very badly insulated. Most have windows, and when you start adding 1" of foam and an air gap to a van you will lose a lot of valuable interior space.

At this point, there is no good off grid AC system for a VAN (minivan, passenger van, cargo van), that is 100% solar / battery powered. You simply don't have enough roof for the amount of panels needed. And a solution that works for a few hours a day is not a proper solution.

my cargo trailer has always had a 5k window unit,my recently purchased house now has some of my solar panels of my trailer as i am always experimenting ,growatt on house now another otw etc etc

 

[Hendo7]

sorry folks i have been posting in the wrong thread
i do wish all you van dwellers the best of luck in getting a ac unit that works with your set upcheers

 

[McCarthy]

What it takes to run a small split AC (only when the sun is out, in Canadian summers) in a larger build:

- 8 large panels (will never fit on a van)
- Still no 24/7 AC
- Only works halfway decently because this vehicle has no windows and proper insulation.
- Build of that motorized slide panel system takes several months of work. Including 8 large panels, converter, batteries, split AC, custom brackets, electronics and cables, I'd say the cost is over $15,000.

 

[Swamplizard]

I was looking at swamp coolers but they only work of dry environment and wont do in S FL. Ended up with a coleman roof model - draws 900-1000w once it's going. I can run it long enough off batteries to cool van before sleep, or on any shore power, or a small genny. Would need a whole lot more roof space and batteries to run it off batts all day or tow a tesla ;-)

 

[JMc]

Our tiny trailer (Chalet A-frame) has a bulky Dometic heat pump that draws 1100W in A/C mode and about 900W in heating mode, so it’s only practical when we’re on shore power. Replacing it with a newer, more compact unit would certainly free up some valuable space, but power-wise the difference isn’t enough to justify the expense and all the work involved. Even at 450W (optimistic) one of these new mini-splits still pulls too much power for battery operation.

 

[Fast1one]

I think some don't understand what VAN LIFE is (topic of this thread). We are not talking RVs or trailers.

Here a few typical images of people who live in vans, many of them full time!

You can find them on most Wal Mart parking lots late at night. Those are people with limited funds, and limit roof space for solar panels, and limited room for batteries.

Money would be much better spent on insulation and ventilation. I don't really understand minimalist Vanlife. Just a little more effort would go a long way without much cost. Going from effectively R0 to R3 is a massive difference. I think its more laziness than money really. Especially the example with the not so cheap Siena minivan!

Not a van but our short school bus went from unbearable to tolerable in 90 degree weather in full sun by adding R7 wool insulation and ventilation fans. Wool can easily be squeezed behind panels anywhere it fits. Make some insulative covers for the windows. Add a roof fan or repurpose the OEM blower motor to provide crossflow. It won't be enough for 120F weather but its a step in the right direction.

 

[Altide8]

I am not sure what the OP intended for this thread. It seems like it has gone in a number of different directions.

Bottom line is that it's going to be very difficult to run any a/c unit on purely solar. It is pretty easy to find hookups/shore power and charge up when driving. I have a renogy dc-dc charger that I use if it's cloudy. 400w of solar. I also use a 300w power supply to help when I need it. Although, I have a meanwell rsp-750 on the way. All of these components are controlled by the Electrodacus sbms40

If you have a good-sized bank then running a small a/c during the night is manageable. I don't know about everyone else but I am not in my van much during the day. The van is a means to spend more time outdoors. I would assume this is the case for most people.. maybe I am wrong.

edit: Also in the summer time I am more willing to pay for a camp spot with hookups. Being in a van you can even use some less traditional and cheaper options such as hipcamp

 

[McCarthy]

Money would be much better spent on insulation and ventilation. I don't really understand minimalist Vanlife. Just a little more effort would go a long way without much cost. Going from effectively R0 to R3 is a massive difference. I think its more laziness than money really. Especially the example with the not so cheap Siena minivan!

Not a van but our short school bus went from unbearable to tolerable in 90 degree weather in full sun by adding R7 wool insulation and ventilation fans. Wool can easily be squeezed behind panels anywhere it fits. Make some insulative covers for the windows. Add a roof fan or repurpose the OEM blower motor to provide crossflow. It won't be enough for 120F weather but its a step in the right direction.

Many of them are also not handy at all. They throw a cot, 5 gal water jug and an Ikea chest into the van and are done.

 

[McCarthy]

I am not sure what the OP intended for this thread. It seems like it has gone in a number of different directions.

Bottom line is that it's going to be very difficult to run any a/c unit on purely solar. It is pretty easy to find hookups/shore power and charge up when driving. I have a renogy dc-dc charger that I use if it's cloudy. 400w of solar. I also use a 300w power supply to help when I need it. Although, I have a meanwell rsp-750 on the way. All of these components are controlled by the Electrodacus sbms40

If you have a good-sized bank then running a small a/c during the night is manageable. I don't know about everyone else but I am not in my van much during the day. The van is a means to spend more time outdoors. I would assume this is the case for most people.. maybe I am wrong.

edit: Also in the summer time I am more willing to pay for a camp spot with hookups. Being in a van you can even use some less traditional and cheaper options such as hipcamp

People living in their vans spend a ton of time inside when it rains or in case they work online jobs on the laptop.

A window unit pulling 720 watt per hour will need 5.8 kw over night. With losses and power needed for other items, you will need 2 x 280 A battery banks. They can be squeezed into a (mini) van, but most won't. You need all the room for other items. Bigger problem is trying to charge 560 A into the batteries. A 30 A DC to DC charger would need 18.6 hours. A 380 W panel would need well over 30 hours.

Ain't gonna happen without shore power and that's what people LIVING in vans don't have. They boondock in random places over night and move on. They don't spend 50 bucks a night on stupid RV parks with hookups. They don't have the money and it would defeat the purpose of saving money.

Watch this guy... fulltime in a cargo van... no AC... he even skipped solar since he moved out of his old minivan... only a high output alternator.

 

[hardtop]

I'm subscribing to the view that adapting an AC out of an electric vehicle is the way to go. Here in the Mohave there was a heat wave at 20F above normal a few weeks ago and I write code in a tent as an overlander. Then NOAA gave a wind advisory of 55 MPH winds for my area and I needed to drop the tent and get into my bunker to work in there.

The bunker is a Chevy Volt and its black on black. It had been sitting in the afternoon sun with windows up and about 93F ambient. The AC cooled the car and myself (sweating) quickly and then it maintained 70F sipping little energy from the battery. That cool air was bliss. There was plenty of cooling power left on the table. Those cars have powerful AC's. This particular car will cool both the interior and the battery with one AC. If you put one of those in your van, it would be absolute bliss.

 

[eXodus]

I think you guys make a general mistake when considering to cool your stationary vehicle off-grid with an AC unit.

In order to cool a car properly in the summer, under sunlight, the stock AC is often at the maximum it can pump out, and my minivan AC for instance, has a really hard time fighting the Florida heat and humidity. When the car was parked in the sun, it takes the AC about 12 minutes too cool the front row down to some mid 70s degrees and that's basically where it stops, running at full blast. Maybe a core cleaning and fresh refrigerant will improve this a little, but not by a lot.

Now, many homes in Florida the size of 2,000 sqft run on a 2.5 ton AC unit. Guess how many tons your average sedan AC puts out. Up to 3.3 tons / 40,000 BTU. All those 2,000 BTU toys won't do crap.

Don't underestimate how much energy it takes to cool down a standing vehicle in direct sunlight with basically zero insulation.

I'm converting a minivan to a camper right now. The inside of a car in 90 F summer temps and direct sunlight can reach over 140 F. Getting it down into the double digits is the primary goal.

This is what I do to archive this goal and that doesn't require me to run the engine or generators:

1.) Buy a white vehicle or one with a very bright color and metallic paint. Both helps to reduce the temperature inside by reflecting parts of the UV and visible light.

2.) Install window tint with ceramic coating, not just cheap limo tint. Install on all windows, even the windshield. They offer films with no or minimal tint. The ceramic coating reflects UV light.

3.) Install window vent shades / deflectors and keep the windows cracked by 1 inch.

4.) Run a fan inside that cools you down.

5.) Find the cabin exhaust vents, remove the flaps, do some ducting to the inside of the cabin, and install large PRESSURIZING computer cooling fans with the highest airflow rating. Good ones move 120 m³/h (that's 70 cubic feet a minute!) Most cabin exhaust vents can be found low, behind rear bumpers etc.

6.) These fans run on only a few watts. Keep them running with the windows cracked even when you are not inside the vehicle. Maintaining 85 F inside a car is much easier than having to cool it down from 120 F.

The fans pump cool air from under the (white) bumper into the vehicle and push the hot air (goes up) out of the cracked windows.

Your recommendations are good but your initial statement isn't

I'm running a 6000 BTU window A/C in my Chevy express Cargo Van for the last 5 years and it never had a problem cooling it down.
Not to 60s - but it could hold 74 during the day.

2000 BTU is a toy, like you mentioned - but all the units mentioned in this tread had 8000 BTU.

Most of the A/C power of a car is gobbled up - because it's leaking so much air while driving - as soon as you stand that need decreases.
My 30 ft RV runs of a 13500 BTU A/C. - while standing - as soon as I drive -I need the Dash and the roof A/C to keep it cool - air leaking is a huge force.
When the engine idles you got may 1/5 of the full power of the A/C available - that why often idling car gets hot inside.

A mini Van is probably the worst scenario for A/C - lots of windows and terrible insulation.
You can approximate one window with 500-1000 BTU. The remainder of the vehicle is 3000-4000

Further -you need to cover the windows OUTSIDE, inside shades do little to prevent heat coming in. They are great to keep heat inside.

 

[eXodus]

People living in their vans spend a ton of time inside when it rains or in case they work online jobs on the laptop.

A window unit pulling 720 watt per hour will need 5.8 kw over night. With losses and power needed for other items, you will need 2 x 280 A battery banks. They can be squeezed into a (mini) van, but most won't. You need all the room for other items. Bigger problem is trying to charge 560 A into the batteries. A 30 A DC to DC charger would need 18.6 hours. A 380 W panel would need well over 30 hours.

The A/C math is just wrong - the A/C runs maybe 20 minute out of an hour. So divide your number /3

I got a 6000 BTU window unit in my Van - it runs of 450AH of Lead - for the last 5 years. 200W solar and 180AH alternator.
The A/C gobbles between 1200 and 2000wh for a night in Florida.

When you hear the anti-A/C vandweller talking - it always feels like I'm doing something impossible I like doing impossible things.
I enjoy the cool Van and looking forward to do this with the 24V split systemin my RV soon

While you guys are still debating if it can be done, we just keep doing it

 

[eXodus]

View attachment 45854
The manufacturer sent the low pressure hose with the wrong fitting, but they also sent the correct fitting. I had a shop in town cut the hose and crimp the correct fitting. Will report back when I get it charged and wired up.

love it! let us know when you get it running.

Was a white cover available as well? Which seller did you buy it from?

 

[McCarthy]

The A/C math is just wrong - the A/C runs maybe 20 minute out of an hour. So divide your number /3

I got a 6000 BTU window unit in my Van - it runs of 450AH of Lead - for the last 5 years. 200W solar and 180AH alternator.
The A/C gobbles between 1200 and 2000wh for a night in Florida.

When you hear the anti-A/C vandweller talking - it always feels like I'm doing something impossible I like doing impossible things.
I enjoy the cool Van and looking forward to do this with the 24V split systemin my RV soon

While you guys are still debating if it can be done, we just keep doing it

Read again. I was talking about solar, not an alternator that needs your engine running all the time to recharge, especially with a weak 200 watt panel. What are you doing at day time when we have 95 F and 90% humidity? Your AC still running just 20 min out of 1 hour? Nope.

You can't run a 6k BTU unit on 200 watts of solar, 400 will also not cut it, past that you will soon run out of roof room on a van, period.

 

[Zwy]

Read again. I was talking about solar, not an alternator that needs your engine running all the time to recharge, especially with a weak 200 watt panel. What are you doing at day time when we have 95 F and 90% humidity? Your AC still running just 20 min out 1 hour? Nope.

You can't run a 6k BTU unit on 200 watts of solar, 400 will also not cut it, past that you will soon run out of roof room on a van, period.

Compressor doesn't run all the time after initial cooldown, the fans do. But I agree, you're not running a 6K BTU unit off 200w of PV or 400w.

Was just a thread the other day with a fella wanting to install PV along with a 12v 2kw inverter on his truck camper. Wanted to run the roof air off it. Thought members were trolling him when he was told it wasn't going to work.

Unrealistic expectations.

I'm really interested in the mini split 12V setup mentioned in this thread. Can't wait to see the testing results. I'd go 24V in my TC.

 

[OnTheRoadAgain]

Your recommendations are good but your initial statement isn't

I'm running a 6000 BTU window A/C in my Chevy express Cargo Van for the last 5 years and it never had a problem cooling it down.
Not to 60s - but it could hold 74 during the day.

2000 BTU is a toy, like you mentioned - but all the units mentioned in this tread had 8000 BTU.

Most of the A/C power of a car is gobbled up - because it's leaking so much air while driving - as soon as you stand that need decreases.
My 30 ft RV runs of a 13500 BTU A/C. - while standing - as soon as I drive -I need the Dash and the roof A/C to keep it cool - air leaking is a huge force.
When the engine idles you got may 1/5 of the full power of the A/C available - that why often idling car gets hot inside.

A mini Van is probably the worst scenario for A/C - lots of windows and terrible insulation.
You can approximate one window with 500-1000 BTU. The remainder of the vehicle is 3000-4000

Further -you need to cover the windows OUTSIDE, inside shades do little to prevent heat coming in. They are great to keep heat inside.

If...........
You only needed to use the AC while sleeping and not all day, that would drastically reduce the battery and solar needed.

I would guess that a 2000btu unit would be MORE than enough to make your nights cool and dry without having to fight the massive heating of old Sol.

During the day stay outside or in the shade. If you absolutely must have AC during the day then the vehicles AC might be an option. Or a big fan and that Aluminized reflective shade netting.

 

[eXodus]

Read again. I was talking about solar, not an alternator that needs your engine running all the time to recharge, especially with a weak 200 watt panel. What are you doing at day time when we have 95 F and 90% humidity? Your AC still running just 20 min out of 1 hour? Nope.

You can't run a 6k BTU unit on 200 watts of solar, 400 will also not cut it, past that you will soon run out of roof room on a van, period.

Like this night - started out with 85 - turned on the A/C - ran it for about 2 hours - then it cooled of enough so that I didn't had to use anymore.

The alternator is my backup power source of charging. I drive every other day anyhow. I hardly stay more then 48 hours in one place.
When we got into the summer - just hanging out somewhere with power or driving somewhere cool.

I don't stay somewhere where the nights stay above 80.

If...........
You only needed to use the AC while sleeping and not all day, that would drastically reduce the battery and solar needed.

I would guess that a 2000btu unit would be MORE than enough to make your nights cool and dry without having to fight the massive heating of old Sol.

During the day stay outside or in the shade. If you absolutely must have AC during the day then the vehicles AC might be an option. Or a big fan and that Aluminized reflective shade netting.

My express Van got the heavy duty A/C option from the passenger Vans- it does a fabulous job at keeping the box cool at idle. I've used it a few times during the day to cool of. Just gobbles a lot of fuel.

 

[Swamplizard]

I picked up a 12-volt water cooled A/C for my boat but have had nothing but problems with it ... it has multiple mini compressors and as things cool it turn them off one at a time...super efficient but very finicky about water pressure, "freon" pressure, battery voltages etc.... it's been a PITA since day one and wish I hadnt bought it. Sometimes too efficient isnt reliable. Keep it simple!