I picked up a new to me refrigerator from CL It seamed to work at moment of buying. Now Im in a kind of in dought.
I know it takes time to cool things down from room temp. Also the bigger they are the longer they take. Now I put 20 gallons of water and beer and gatoraid in ref. 2-5gl corny kegs 1-3gl corny keg 1-5gl glass carboy the rest cans bootles and gatoraid. Temps were The cornys 70 degrees, the carboy gardenhose cool. beer and gator out of other fridge. And 4 water filled milk jugs in the freezer.
Its been 36 hours Ive never heard the compressor stop running and its 43 degrees in refrigerator compartment 10 in the freezer.
My mini fridge takes about 24 hours to cool down a 5 gallon corny to around 40F. And that is with a full already cool corny next to it working as a thermal buffer. So no, I don't think your cooling times are unreasonable. Especially considering the massive amount of liquid you put in at once, with nothing cold already in the fridge.