inverter 220 volt?

Autotransformers are available at Allied Electronics. Their part number P-8689 is what you want. Note that if you're using an autotransformer, you must keep whatever you're powering completely isolated from the rest of the world, because one leg of the low side is tied to one leg of the high side. (There is only one winding in an autotransformer, no "primary" and "secondary".) If this might be an issue, go with an isolation transformer which will be heavier and more expensive, but safer. Allied stocks those too.

• Allied Electronics

I'm with Chris as it's more cost effective to go with a genset, pump into a storage tank, then pressure the house system with a seperate pump from the storage tank.

If your wanting to stay "off grid" then consider using RV 12v Surflow pumps, 3gpm @35psi, about $60eh at Camping World, for a pressure pump. Need more volume, parallel two pumps into a common header or you can set them up with a bladder tank (less pump run time, more volume).

If you buy a electric start genset it's easy to set them up for automatic start/stop depending on the storage tank water level.

I've been all solar on my RV for the past 4yrs. I hate gensets as it disturbes my peace of mind when I'm in the backcountry.

While the genset is pumping water you can also wash/dry cloths. You can put in a manual start in the laundry room for wash time.

If you like being off grid, then consider a used VW diesel to power the generator as they burn about 1gal #2D hour with about 24hp @ 1800rpm.

Anytime you use a invertor it's gets expensive real fast. Use straight DC where ever you can.

I like talking solar so if you want more info let me know.

T_Bone

i want to run two banks of batteries. then call on them together when the pump is needed for 10 minutes or so, every once in a while.

the rest of the draw on the system would be minimal compared to the draw the pump produces.

dont have the clams for the size inverter i need,
not yet anyway-- am starting to collect the batteries.

Scott