Hi,
I have a motorhome, and the jacks draw about 40 amps for only a few seconds to level it, so if run a full minute at 40 amps draw, it would still be less than 1 amp hour.
The pump draws about 7 amps per hour, while pumping 2 GPM or 120 gallons. So water pump is also insignificant. (unless you have a 120 gallon tank, then it would be about 2 AH per day)
What really consumes the power is the refrigerator, CO meter and propane leak detector. Together they draw 0.8 amps and 1.2 amps while the refrigerator is on. This works out to about 35 AH daily.
If you are really concerned about the amp draw while loading the camper, try to plug it into the truck for as much time as possible, and the alternator will supply all the power, and charge the battery slowly at the same time.
Chances are that the truck to camper battery wire is really tiny. Maybe #12 wire? Perhaps #14 wire? Upgrading to #8 wire and a twistlock 30 amp power plug (so it will not accidentally get connected to household power) will allow the alternator to fully charge those large golf cart batteries in less than a 5 hour drive. With #12 wire, the amp might move at 12 - 15 amps per hour, or a 10 hour drive can take them from 30% state of charge up to around 70% full. 10 HOURS!.
My real recommendation is to install some solar panels. A pair of 140 watt solar panels will put out 8 amps to the batteries several hours per day, figure each one will put back about 40 AH daily with a PWM controller. Don't expect a lot more with the much more expensive MPPT controller, the amps back into the battery will only be about 5% more per day.
With the solar panels, all trips will start out with full batteries, and you might use say 100 AH daily. Instead of discharging them over 2 days, you will take out 100 AH, put back 40 - 80, then take out 100 AH, and put back 40 - 80. You can keep doing this for several days before needing to run a generator.
Another thing to help heat the camper is a Olympic Catalytic heater. It does not consume any 12 volt power, but you do need to leave a roof vent and kitchen window open a bit, just like when you are cooking with the stove.
Have fun camping!
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
If there's a WILL, I want to be in it!
I havn't been everywhere, but it's on my list.
Kangen.com Alkaline waterEscapees.com