CAn you replace a 13 amp fuse with 15 amp fuse?

It will work but will not protect the circuit as it should. By design, the circuit should have a maximum of 13 amps, but with the larger fuse in place, currents of 14 and 15 amps can occur without blowing the fuse, and this flow could damage parts of the circuit.

It would be much safer to use a lower value, which would lead to more blowing of the fuse but no damage to the circuit being protected.