You say you heard a motor run when you put in the fuse and thought it was the Fridge, Do you have fans in your fridge, either inside or out? (A residential fridge would need a lot more than 15 amps and an Absorption fridge has no motors, unless it has a fan or 4 (mine has 4)
A better way to test fuses.
Use a test liht, an automotive test light considting of a device that looks like an old fashion ice pick save the handle is clear or translucent colored plastic, and has a wire coming out of it.. GROUND the clip on teh end of the wire (Find a good ground near by) and on those blade fuses there is a small "Window" on the ends of the fuse.
Bright-bright = good
Bright-Dark = bad
Dark-dark = no power to fuse no test (This shoudl not happen on the house fuse panel but can on the chassis panels if the ignition is off).