The original (and most lp replacement friges.) do not have that much cooling capacity. The warmer the outside weather, the poorer it gets. To be assured that I do not have alot of food go bad, I fire up the unit a day before I am going to have to use the frig. If I do not have that time, I buy a 7 pound bag of ice and put it in the frig. then I buy the groceries and fire the unit up. The ice partially melts and give the unit a head start on getting cold. I also installed a 12 volt
brushless computer fan in the vent space directed up the coils. Switch is by the side of the frig as is the indoor outdoor thermometer to keep tabs on the frig. temp. I turn the fan on if the frig gets over 36 F.
These fans are cheap fairly quiet units you can salvage out of an old computer power supply or buy for low cost.