I talked to a few outfitters who have installed and used Kingtec’s rooftop AC’s and likes them. My KTD-1 showed up yesterday, looks pretty good. Won’t know how it works for a while. The new KTD-2 has even better specs, and only 48A draw

 

Price and performance are subpar on all these 12v units. They are under powered compared to a traditional 120v rooftop unit. To the point of not doing much for you when its actually hot out. So I figure for the 2-3k price difference just get a 120v unit and put the savings toward more battery power. Which is overall more useful.

 

I’d like to see a 120V that is more efficient than a Kingtec KTD-1/2, or even some of the other ones like Nomadic.

13.5 Amps for a 120V 13.5k BTU unit is 1620 watts/he.

50 Amps for a 12V 9.8K BTU unit is 600 watts/hr. Much smaller footprint as well.

 

Are you more efficient if you cant cool the van? It would need to run constantly and still not do the job. It ends up making no sense. These units were mostly designed for over the road truck cabs. Blowing directly on the bed area in a small truck cab. They were never meant to try and cool a van. If only using AC at night to sleep I guess that could work. But then still....price difference for that purpose is really silly.

We are obsessed with the idea of a 12v AC. And these companies know that. But they just arent there at this point in time. 3-6k for an AC that in no way will cool a van down when its hot out during the day. When you can get a 120v for 1k and use the savings towards battery power that is still beneficial during the other 95% of your van usage time.

 

The units I mentioned are 8-10K BTU, and under $3000. More expensive yea, but space and energy efficiency come at a premium in such a small space.

on top of that, they can be run 2-3x longer than the AC units for the same battery usage, which will provide more net BTU cooling.

I’d rather have my 12v in 6 hours a day than a 120V on 2-3 hours a day.

 

Assuming above data is correct for 12V air conditioner, it should run about 50% longer when compared to PowerSaver using a high quality inverter (also assumes fairly large lithium battery bank). With lead batteries estimates are skewed too much to be accurate.

A rough estimate for budgeting would be that 12V A/C would run about the same duration on 400 Ah as a PowerSaver with inverter on 600 Ah. Again, assumes 9,800 BTU/hr cooling on ~600 Watts.

 

I would take their numbers with a grain of salt. The idea that 600w is going to cool a van seems unlikely to me. Ive seen enough user reviews on these DC units to know theres no way they are actually outputting 10k btu on the high end. Which would be right on the borderline of cooling a van on a hot day anyway.

And yes a 600ah lithium bank is what you would want to run an AC all night. A 600ah battery and 120v AC comes out cheaper than a 400ah bank with one of these DC units.

 

Well I haven’t used my AC yet, but when I’ll do I’ll post results. It’s quite possible their ratings are false, but I’d hope not. We’ll find out. The construction seems well made so far.

 

Did you use an adapter to install on the roof or just use the foam they sent? I've been waiting for the adapter but getting impatient.

 

Following looking for updates. I plan on installing the Nomadic 3000 roof top 12V in my off grid 600AH design. Hopefully i'll be able to run it at lower settings. Planning on getting the Ingot silver color and insulating very well to help reduce solar heat gain. Can't do much about the heat gain thru windows if you enjoy looking out during the day.

 

In my personal experience with the Nomadic, you're battery bank is more than enough to run on low for quite a while. I find the unit is pretty quite outside, very doable noise inside if on low, but fairly loud on the high setting. Park in the shade, cover up the bigger windows. I also got 3M clear window film installed on my windshield and that's helped a ton with preventing as much heat gain in the cab so the AC doesn't have to work as hard.

 

We have the Nomadic Cooling 3000 12v (11,830 BTU claimed output), and honestly, it has been a big disappointment. It doesn't lower the overall temperature in the van measurably by even a single degree in most cases when we've tested it. It's nice to sit or stand right under it, but that's about the extent of its usefulness. We have 800 amp hours in the battery bank, so it lasts quite a while even on full blast, but even on full blast, it does not have a meaningful impact on internal temperatures. I would rather a shorter run time and a more effective unit. We live full time in our 170" WB Sprinter. So our cab is on the larger side. Maybe it would have a measurable effect in a shorter wheelbase vehicle, but from my experience, I would save the money and avoid the brand altogether. Our Maxxair with windows open is far more effective at cooling the van than our AC unit. We've tested in every configuration we could think of with every window blacked out - vent on/off, windows open/closed, all produced equal or worse results than just running the Maxxair at full blast with the windows open and no AC at all).

 

Not sure if you came here just to put Nomadic on blast, which is totally fair, but where do you live? Can you jam a thermometer into the outlet and measure the outlet temperature vs ambient?

I have a similar unit (self-imported, not branded Nomadic) and while the airflow is definitely not great, I tested it to 45 degrees at the outlet vs 78 deg ambient (33 degree differential), which is pretty fair. Depending on the relative humidity, most cars are built to cool somewhere between 35-50 degrees below ambient, while most home units are sized to provide only a 15-20 degree differential. If can get get good temperature differential at the unit, you can "help" it by adding a small fan inside the van to circulate air, which is where my unit is the weakest. Insulation helps too.

If you think the unit isn't functioning to spec, any car mechanic can run through the standard diagnostic procedure, or you can buy the $100 gauge set if you're mechanically inclined. The procedure is exactly the same, and the high and low pressure service ports even the same. Good luck.

 

The search continues for a low profile 12v AC unit 😩

 

After watching this video showing the Dometic RTX 2000 in a van with an uncovered slider window, front cab exposed, no insulation in back doors, something must be wrong with your Nomadic Cooling unit or it simply doesn't perform to spec. Your unit should be performing much better than the unit in this video.

 

Again, the biggest difference between his test circumstances and mine is the sun. He mentioned right at the beginning that he's testing the unit in the shade. He's also probably in a short wheelbase, so less internal volume to cool. He also mentioned that by the time he measured the 77 degrees toward the end of the test it was only 84 degrees outside.

So, he was about 7 degrees below external temperature after an hour in the shade (which I don't think is all that impressive, but again, realistic expectations and desired use case are a big part of this, so I acknowledge that I may have came in a little optimistic). He mentions later a further internal temperature drop using the "boost" mode, but he doesn't say what the external temperature then is, so it's impossible to guess the performance unless I missed something in the video.

I bet (but don't know for sure, because I have not tested this scenario) that mine could perform similarly under those conditions. I may post an update here soon in case folks are interested.

The point I was making earlier is that even if the outside temperature is in the high 70's, the internal temp of the van will be easily high 90's or more on a sunny day after several hours of sitting in the sun. My Nomadic 3000 unit DID keep the van down to about ~84 degrees in the windows closed tests (it was roughly ~76 degrees outside), which is better than high 90's for sure.. But opening the windows and cranking the vent fan kept it below 80 (roughly 2-3 degrees above outside temps). Which was better than the AC's performance. Therefore, in the sun, on a warm sunny day, the AC effectively becomes irrelevant.

Note: Our cab is also not separated, but we did have reflective shades up for the tests.

 

I think these 12 volt air conditioners will never replace the vehicles 30 K btu air conditioning system but I think that if someone pre-cooled their van with the vehicle air conditioner or used both then switched to the 12 volt air conditioner it would keep the temp comfortable.

 

The unit I have is the Nomadic 3000 12 v in my sprinter 2500 144 reg roof this is for my work van and if your not right under it blowing on you works until you have to move away from it and it like not even having ac for the rest of van and it is insulated if I was to do it over again, spend the money on the batteries and get more power with the 120 rooftop AC this is in Florida tho and now only a year into it. AC is having problems sent the new control panel still doesn’t work. They are trying to figure it out as we speak way to find out the hard way. Once again, we have to upgrade it especially if they can’t fix the problem once again only a little over a year old talk about a talk about throwing money away and got charged for new control that was said to have problems with some and still having same problem so it’s not the control hope the refund for the control