Has anyone installed a 12V RV air conditioner?

[patti19064]

I’m considering something like the Dometic RTX 2000, but there are not many reviews available. We have a 2018 Forest River Arctic Wolf 5th wheel. Our traveling style often consists of starting and ending a trip with two long driving days, to get away from the East Coast to a vacation destination, using my PTO. It is nice to break up the travel day with an after lunch or mid-afternoon nap. We stop in a rest area/Cracker Barrel/Walmart for the first night. The 5er allows us to use the bedroom and bath without putting out any slides or having hook ups. We have solar panels and three Battle Born lithium batteries (300ah). The challenge is when we are traveling in 90-degree weather; the bedroom is warm with only the open window, Dyson fan and fantastic vent. The trailer is configured to be able to add a second air conditioner in the bedroom. The 12V seems like a great option for us. We only want to cool down the bedroom area for sleeping. It seems the lithium batteries should be able to power this unit, unlike standard air conditioners.
I’m not interested in changing our style to shorter travel days with campground stays. I only get a limited time off work; more travel days would mean getting to the destination only to turn around and head home again! We would also like to do some boondocking.
I was wondering if anyone in the group has any experience with 12V AC. I look forward to learning more about these units.

[brucemc]

I've never researched these 12vdc units, but would think you'd need far larger wire (amp capacity) than is currently routed to the vent. The wiring is 14 gauge at best, then add in the distance and number of junctions from the batteries. 14 gauge is good for 15 amps, but after factoring distance and all other consumers of that branch, you might not be able to draw anywhere near the amps required for the AC with the existing wiring.

What is the amperage draw of one of these 12v units, BTW?

I tried to run a 250w inverter for a 115v TV from one of my 12 branches; that inverter alarmed with low voltage given a load less than the rated wattage. Granted, it was a MSW, but still... I changed gears and isolated a 115vac branch to run the TV from my 300w PSW that is mounted a foot from the power distribution center, and used 8 gauge wires on the 12v side. That 115vac line is also switchable to the mains when I have shore power, using a break before make switch.

Good luck!

[llr]

No experience with them but the 1st thing I would check is the current draw, I suspect it will need larger wires ran which could be a challenge.

[MR.M]

Originally Posted by brucemc

I've never researched these 12vdc units, but would think you'd need far larger wire (amp capacity) than is currently routed to the vent. The wiring is 14 gauge at best, then add in the distance and number of junctions from the batteries. 14 gauge is good for 15 amps, but after factoring distance and all other consumers of that branch, you might not be able to draw anywhere near the amps required for the AC with the existing wiring.

What is the amperage draw of one of these 12v units, BTW?

I tried to run a 250w inverter for a 115v TV from one of my 12 branches; that inverter alarmed with low voltage given a load less than the rated wattage. Granted, it was a MSW, but still... I changed gears and isolated a 115vac branch to run the TV from my 300w PSW that is mounted a foot from the power distribution center, and used 8 gauge wires on the 12v side. That 115vac line is also switchable to the mains when I have shore power, using a break before make switch.

Good luck!

I agree wire size could be a problem but have never seen anything less the 12 gauge run to AC'

[Aussieguy]

look at variable speed mini splits or under bunk a/c
or wait a while for the furrion chill cube to be made public for aftermarket installs


They are 120v but can use LESS power for startup and solar/battery consumption
they have a inbuilt inverter (for their own speed control)
Their inbuilt inverters are NOT able to be used for powering other appliances

installation is easier + you can use a standard RV style INVERTER
you install to power other things 120v when not using the a/c
They have been using mini splits for several years now and is a proven way to beat the heat.

as others said... 12v wiring will be the problem
depending where your battery is located can cost you a lot $$$$ just for the wiring
last time I looked the a/c were around 40amps (12v) running amps
then 20 foot each way of wiring = 2 or 4 awg ($150 )


how MUCH solar you got plus any DC-DC ?
if you can produce 40-60amps you can run an a/c even while driving... turn the thermostat to 78 or higher just to get rid of heat buildup

get your batteries charged and then use subsequent solar and maybe some battery to cool down the rv.

My preference would be look at mini-splits ... Much cheaper and can run on around 600w whe
EG4 has one you can simply plug in the solar wiring AND can also have 120v.

+ easier to service
+ frees up roof space for a couple extra panels
+ less shading on roof


cooling down the RV before you loose solar power would be the best option
that way you are taking the least amount of battery power.

[patti19064]

From the manufacturer:
Only uses 19 amps of energy in eco mode – power consumption ranges between 10 amps to 58 amps.
Innovative speed controlled inverter compressor reduces energy consumption.
1700 W/ 12 volt / 6,824 BTU. (Recommended to be used with a battery bank of 180 amp hours or larger.)
Compact size leaves more space for solar panels and other things on your roof.

We cannot start the existing AC in the trailer on battery. We might have enough battery power to run the AC for a couple of hours, but could not start it to pre-cool. Of course we could start with the generator, but that has its own restrictions-we can't be doing that in a rest area. I'm looking for simple and inconspicuous. That's also the problem with a mini-split-there is a unit that has to be outside the trailer.

The battery bank is located in the storage bay under the bed, so maybe 10 feet of run. We already pulled off the wall behind the bed once, to add insulation, so feeding new wire may be doable. I don't know what the existing wire gauge is-we'll have to check.

Thanks for the input.

[patti19064]

We have 480W of solar, Victron MultiPlus 3000W inverter, and a soft start on the 15000W AC.

[Larry-NC]

Originally Posted by MR.M

I agree wire size could be a problem but have never seen anything less the 12 gauge run to AC'

Umm, AWG 12 is good for a 120 Vac air conditioner.

This thread is about 12 Vdc air conditioners while boondocking in a parking lot.

These reviews suggest that the power requirements could be up to 65 amps. (The reviews cover smaller units for vans up and larger ones suitable for the OPs fifth wheel.)

Thinking that AWG 4 or so would be needed.

Also thinking that the draw would drain the OPs 300 Ah battery in 5 hours of operation (10 hours at 50% duty cycle).

[Aussieguy]

you need to be careful sizing the wire
most calculators want the total run from battery to the appliance then back to battery

10 foot becomes 20 foot then add the extra for corners etc
25 foot.... may be a good starting point
https://www.wirebarn.com/Wire-Calculator-_ep_41.html

max amps 60 @ 12v = 2awg
make sure you find out max wire size you can connect to the a/c

the output 6000 btu not nearly enough for a 2018 Arctic Wolf 285DRL4 (your profile)

[Aussieguy]

your 5th wheel has potential to have enough solar so you can run a a/c for may hours
you just need the right combination of panels / Inverter / battery

unless you find a real efficient a/c you'll nee a LOT of battery for overnight
Mini splits and window units that come with the inverter controller are capable of using just 400w after initial cool down.

do yourself a favor and investigate the other alternatives
lots of people .... on this forum and elsewhere have used the mini splits
search youtube for how to install
https://www.google.com/search?client...ini+split#ip=1

There is a reason the 12v units are not widely used....
big $$$ for a small unit that won't cool good in anything much over 20foot

$2000 spent on panels / controller and battery would a long way to improve what you have

[jlankford]

Just FYI, it looks like Dometic provides a wiring installation kit for the RTX 2000 consisting of a 26' long harness using 4 awg wire and 80amp fuse block.

...and the kit is required to be used for warranty coverage, so no point trying to engineer your own wiring run.

[reidfo]

What about installing a typical 120V AC with a soft start, but say 13,500 BTU or less? You can likely start that off your batteries/inverter.

[Eagle1967]

Originally Posted by patti19064

The trailer is configured to be able to add a second air conditioner in the bedroom. The 12V seems like a great option for us. We only want to cool down the bedroom area for sleeping. It seems the lithium batteries should be able to power this unit, unlike standard air conditioners.

First from what i read i don't see much of a difference in amperage usage.
12 x 100 or 120 x 14. (from what ive read 100 amps on these 12 volts at 100 degrees)

I don't understand the be able to power the unit unlike standard air conditioners.
You said you have a Victron 3000. and a soft start. i power the air conditioner without a problem with this combination.

[corn18]

Originally Posted by reidfo

What about installing a typical 120V AC with a soft start, but say 13,500 BTU or less? You can likely start that off your batteries/inverter.

This is a good idea. I assume the OP has ducted AC. What we do at night is close all the overhead vents except the bedroom. I replaced the fixed vents in the main living area with the kind that can be directed and closed. Then we close the bedroom doors. That means all that has to be cooled is the bedroom. I also installed a microair thermostat in the bedroom. It only runs the front AC. Now we have a bedroom AC unit that is only cooling the bedroom. When setup this way, the bedroom cools off real quick and stays cool without using a lot of AC.


I have 600Ah of LiFePO4 and 1600W of solar. The inverter is a Victron Multiplus II 3000VA. My system can start and run the 15k BTU AC unit without trouble. We can easily make it through the night with this system.