Arrived a call at 2 homeowner was not at home call them they were 15 minutes away they showed up at 2:15 sound system not running found blowing fuse an air handler breaker in system ran for about 10 minutes then shut down but did not trip breaker low voltage traced wires on low voltage yellow wire found blue pressure switch wire occasionally touching cabinet repaired wire check system unit is working properly at this time charge a half hour labor per John