ACs, Batteries and gennys

[newmarokie]

I've about many on here running their AC on batteries. Would a bunch of you weigh in on the size and number of ACs that you have and how long you can run on battery power? That would also need to state how many Ah of battery you have on board and what the charging capabilities are (genny size and solar supplement)

 

[Kevin D Pem]

I can tell you there are to many variables!

I had a 21' silver Line with a 5000btu A/C Keeping the rig at 74 to 76 four LA GC2 batteries would get me four hrs before the inverter kicked out! When it was in the 105deg range.

Factors to consider! I have not had a rig that was as easy to heat or cool at anytime sense then.

I used a home built poor boy generator to charge the batteries. At that time I had no solar!

 

[newmarokie]

Thanks Kevin. As we have talked before, my coach won't operate the ACs unless I am on shore power or my 8K genny. I am fixated on operating my ACs on batteries. I know there are always compromises that have to be made(I think I have seen you state that a few times). I see Joe and Neal have dual 3k inverters and can do that. I just can't make the numbers work on power requirements for those setups. Going down the road using nothing else can work, but I see them be a challenge when parked. Like Rich has said, to go to 48v, you would need to maintain a smaller 12v system to operate the 12v systems on the coach. And to top it all off, my DW doesn't do compromise very well.

 

[Kevin D Pem]

You likely won't hear this for some time, but there are A/C units that are solar friendly. I don't know if they are available for the RV market, but I wonder if the monetary investment to add enough solar and batteries. Would not be better spent on a mini split installation instead!!!

As RVs go,you would be a pioneer with such an install. Of course,you would benefit greatly for your efforts!!!

 

[MemoriesByTheMile]

I have often wondered why RVs keep using these dometic/coleman rooftop A/C units. Some older diesel pushers had a/c units in the basement area that were ducted into the coach.
If I were to build a unit from scratch the idea of a mini-split and its efficiency would seem logical. Just wondering how the components in a mini-split would fare from the abuse of driving down a pot hole filled road.

 

[Richpatty]

I have the front AC tied back to the inverter (although I put in a switch to flip it back to shore power) with 800ah of lithiums. It is hard to put a number on the amount of hours I can run, as it depends on temperature, sunshine (as I have solar) and driving. If I am driving on a sunny day, between the solar and alternator, I can pretty much go all day. If stationary with sun, I bet I could get several hours, but I have never tested it.

I hope this helps.
Let me know if I missed anything.
Rich

 

[Kevin D Pem]

I have often wondered why RVs keep using these dometic/coleman rooftop A/C units. Some older diesel pushers had a/c units in the basement area that were ducted into the coach.
If I were to build a unit from scratch the idea of a mini-split and its efficiency would seem logical. Just wondering how the components in a mini-split would fare from the abuse of driving down a pot hole filled road.

Only difference I know of is one was designed in the 50's ,and the other much More recent!!! I don't know if they use a capillary tube or expansion valve. One uses an old school 110 compressor, while the other uses a VFD and 3phase brushless motor.

 

[newmarokie]

Yes, memories. I just recently saw, I believe, an older Monaco with the AC in the basement. I would guess maybe the design process gave way to rooftop units for two reasons. It frees up basement space, and rooftop units should get better airflow.