A 15 amp household outlet will run the fridge and keep the battery(ies) charged.
A 20 amp household circuit is better. Be sure you know what outlets INSIDE the house are on the same breaker. They count toward the total load.
Contrary to what some have said; you can run the air conditioner on a 20 amp circuit as long as nothing else is on it. I wouldn't do it for an extended period, but for testing or finding out how to set the thermostat (or loading for a trip) it will work.
My Titanium is in the back yard with the A/C running right now. Admittedly it is on a 50 amp box that was installed specifically to service the RV, but the point is that it is running through a Progressive Industries EMS box that very accurately tracks the amp usage on each leg of the supply. My 15,000 BTU unit pulls 14 amps when starting and 11 amps when running. Day after day. 96 degree weather. Afternoon thunderstorms and high humidity.
Some people seem to make up "rules" as they go along.
Formerly posting as "littleblackdog"
Martha, Allen, & Blackjack
2006 Chevy 3500 D/A LB SRW, RVND 7710
Previously: 2008 Titanium 30E35SA. Currently no trailer due to age & mobility problems. Very sad!
"Real Jeeps have round headlights"