Can someone tell me why our air conditioner keeps blowing the fuse? We have checked everything possible transformer,contact,thermostat and the list goes on. It will run for about 30 seconds then cut off. Any help is appreciated.

Is it blowing the fuse in the furnace, or a fuse in the disconnect outside? If outside, most likely either the compressor or fan motor is going bad and drawing high amps causing the fuse to blow. It could also be as simple as a bad capacitor for the comp or fan motor.