Fuses and circuit breakers should not blow or trip. Check the breaker in your electrical service panel to identify which areas in your home/office the tripped breaker supplies service to. Check to see if the breaker feels warm to the touch. (NEVER touch wires or wire connections in your service panel. High voltage is present) Breakers should not be warm or hot to the touch. In the event the breaker is warm/hot to the touch, this could possibly be an indicator of a weak breaker. Contact a licensed electrician. Should the breaker feel ok to the touch, you could try to reset the breaker or replace the fuse. If the breaker or fuse trips/blows again, you will need to contact a licensed AC contractor like ourselves to diagnose the problem safely and correctly. There could possibly be an issue with a loose electrical wire, the unit could have shorted to the ground, or the compressor could have failed. Electricity is nothing to play with- ALWAYS use a licensed electrician or AC contractor as indicated.