Is the AC connected to inverter on 400?

kbdigitiqe

I know on our 320 it’s not even possible to turn on the AC when on battery, is it the same with the 400? Meaning battery limitations aside is the AC unit even operable when not on shore power?

Thanks!

Mouseketab

No, the air conditioning is not hooked to the inverter. No air conditioning unless on shore power or generator.

RFraer

The inverter is only 1200w. Even if it was connected you would need 2000w. To run it for any length of time you would need more batteries and solar.

TomCanada

In addition, if you did manage to hook up to your A/C to run on a larger inverter, when you run high current on AGM's or lead acid batteries, your capacity decreases greatly.  Capacity is spec'd assuming a 20 hour discharge rate (called 0.05C).  The rule of thumb is if you run at a current where you'll discharge your battery completely in 1 hour instead (which you would definitely do with something as power hungry as an A/C unit), you'd lose about 50% of your capacity.

Using Tab 400 as an example,
- Stock batteries (224Ah) running at 11.2A (0.05C), gives you 224Ah/11.2A = 20 hours of capacity
- Stock batteries (224Ah) running at 224A (1C) about 2700 watts (a little more than the Tab's A/C unit, but also accounts for inverter inefficiencies), gives you 224Ah/224A * 0.5 (capacity drop due to high current) = 30 minutes of capacity (instead of 1 hour).

On top of that, you can only safely discharge your batteries 50-80% (depending on how you monitor them) so you might be down to about 15-24 minutes of A/C run-time, assuming your inverter was large enough and you were able to hook it to your A/C.

Finally - the A/C unit may have some initial high current during initial startup that trips your breakers and/or blows fuses.

Overall - not really a great idea - the only way to really run an A/C off the grid is using a powerful enough generator that can supply the juice needed and can handle the startup currents.  I'd just crack the window and run the fan.  Then again, I don't live in a climate that needs A/C for more than 3-4 months of the year, so I'll just clam up here

kbdigitiqe

@TomCanada thanks. We are installing 340ah of Li batteries and I was really just hoping for a way to run the AC for 15-20mins after we get off the road on a hot day to cool down the trailer quickly at the camp site for the doggos. Sounds like not possible without a generator which we absolutely detest so that’s a little bit of a bummer. Cheers 

EDIT: yahhh didn’t realize the AC was 2000 watts 🤦‍♂️

AirBoss

"Poor Man's" option...

Get a nice tabletop fan and put a large bowl of ice next to it. The 'ol swamp cooler trick may help a bit. 

Tampakayaker

AirBoss said:

"Poor Man's" option...

Get a nice tabletop fan and put a large bowl of ice next to it. The 'ol swamp cooler trick may help a bit. 

That and the big push about a year or so ago using a styrofoam ice chest, a fan, ice, and some ducting. Works best in a drier less humid area.

And on the opposite end is the heater made using clay pots and tea lights.