Inverter to use air conditioner - R/T 200V

[Horseshoecat]

Still learning new things about our 2000 Roadtrek 200 Versatile.

We upgraded the battery to a Renogy 200ah gel battery with all updated electrical - converter and charger, UPS, and generator switch. All are working great

What is the feasibility of using an inverter to power the rear deck 6000 BTU air conditioner when shore power is not available? I have seen some of the inverters come with direct wiring to the battery, alligator clips, or a 12v cigarette plug. Any comments on these?

The air conditioner draws about 500 watts.

Any information or guidance would be greatly appreciated .

Thanks.
HorseshoeCat

[rowiebowie]

A noble, but impractical goal. You'd need at least a 2000W inverter and 600 amp hours of useable battery to run even your small ac for 8 hours. And then you'd need a lot of time and power to recharge your batteries.

[jakegw2]

This is do-able, but your gel battery will be hard-pressed to provide you with anything more then about 2.5 hours of AC and the high current draw will reduce it's lifespan.

If you had the same capacity with LiFEPO4 you could reasonably expect a solid 4 hours of usage with a 500W AC.

These values are for full-duty cycle. If you are somewhere with a moderate temperature where the compressor only needs to run 50% of the time you might increase these times by an additional 75%.

You will of course need an inverter capable of handling the locked rotor amps which will probably mean you will need around a 2000W inverter as rowiebowie stated.

You will not, without additional battery capacity, be able to run the AC overnight. This might not be the end of the world depending on your camping conditions. In the NE using AC on battery during travel stops or even to cool the vehicle down in the evening handles most of our AC needs since the outside temperature cools down to comfortable levels in the middle of the night. If you are trying to sleep comfortably in the south you will need full-duty AC for about 9 hours to really be happy (400A LiFEPO4 or about 600A of AGM to achieve this).

[booster]

I seriously doubt they would ever even get near 2.5 hours even. Figuring 15% inverter inefficiency and 11.5 average running volts gives 50ah per hour. I have never tested a gell battery for voltage drop but my guess is that it will be similar to AGM so below 50% SOC will be spotty to run the AC, especially if the compressor cycles. Of course this assumes no other power use in the van at all and that the battery was really at completely full when starting and in good condition.


I would guess about an 1.5-2 hours and shorter battery life, but that is just a guess.


An alligator clip inverter wouldn't be able to provide the amps needed with that kind of connection unless they were jumper cable size. As was mentioned by others a pure sine wave inverter of 2000 watts would be best, but a 1500 would probably do it if the AC is really only 500 watts.



Lots of information on running AC on batteries on this forum, but the short version is that it can be done but it isn't easy or inexpensive to do.