I need advice on powering the A/C...

[Highway Yacht]

I am removing the stock 10 ton A/C unit in the back of the bus and installing (2) rooftop A/C units with heat strips. I don't plan on using the coach anywhere that doesn't have shore power so I'm not really wanting to deal with battery banks or a gensets. My question is, what is the best way to power the A/C while driving from home to the campground? Can I even do that without the battery banks or a genset?

[FloridaCliff]

You can use an inverter like the 4024 while underway.

That is if you have a big enough alternator.

Cliff

[Tenor]

Cliff is right.
If you have the big 24V alternator, a Xantrex SW4024 will power the 2 AC's.  I'm going to use 2 smaller batteries for starting the bus and use the 2 8D's for house batteries/inverter batteries while going down the road.  The 2 smaller batteries will be mounted where the old AC compressor used to be.  Good luck!

[Highway Yacht]

Yes, I do have the big 24V alternator. I had 2 8D batteries for cranking the bus but changed out to 2 Group 31 batteries when the 8D's went bad. The 2 Group 31 batteries start the bus just fine. So if I use a 24V inverter, then I will need to connect it to a couple of batteries outside of my cranking batteries? I can't help but wonder how the bus supplied the power to the huge 10 ton stock unit.

[Sam 4106]

Hi jlink,
I would forget the heat strips because the A/C blowers put out so much air that the wind chill is greater than the heat supplied. I would either use 2 small electric cube heaters for heat or better yet get roof heat pumps for a combination A/C and heat if your use will be above 40 degrees. We have a heat strip that never gets used but the two cube heaters keep us warm down to the teens and the cube heaters cost less than the heat strips.
Good luck, Sam 4106

[TomC]

The original bus A/C was powered by a large 10-20 ton belt driven compressor.  The large alternator was just used to power the two 1 horsepower blowers (a house typically has a 1/3hp blower for the furnace).  You'll need at least the two 8D's for storing the power when you're idling.  I would suggest you use instead of the 155lb 8D batteries, you use the 220amp 6v batteries that weigh in at a more manageable 80lb or so.  You'd use 4 6v to equal the 2 8D's.  Also spending the extra money for AGM batteries is well worth it since they don't gas (never create the corrosion on the terminals, or explosion potential), can mount sideways, don't need water ever (they're sealed).
I personally have a 10kw Powertech generator powered by a Kubota 4 cylinder Diesel to power my A/C's going down the road and when I dry camp.  I set up my bus with the idea to be self sufficient for a week.  To do this, I have 130 gal water, 85 gal gray water, 45 gal black, and 20 gal propane (powering just the stove and furnace).  Since I live in L.A., the A/C's are used going down the road-like last summer going to Mammoth in over 100 degree weather-while it was a comfortable 75 degrees inside-and that was running only two of the A/C's-much to the credit of the 2.25" sprayed in foam insulation and tinted windows.
On the subject of heat strips, yes they work if you close the vents on the A/C's almost all the way to slow down the air speed, but what is irritating is that it takes at least 5 minutes for them to warm up to create the heat-mean while you're putting up with swirling cold air around you.  Leave the heat strips at the store and buy a couple of good portable room heaters with tip over shut off. I have found that at a 50 amp hook up, two will pretty much keep the bus warm in down to freezing weather-with the propane furnace kicking on only if the wind kicks up.  Good Luck, TomC