What was found
(CAN) ON A SHORT FLIGHT *RED* APU FIRE CAS POSTED AT FL190. CREW FOLLOWED QRH, DISCHARGED FIRE BOTTLE, DECLARED EMERGENCY AND DIVERTED FOR LANDING. FIRE TRUCKS WERE WAITING FOR AIRCRAFT ON LANDING. AIRCRAFT LANDED WITHOUT ISSUE AND POST FLIGHT INSPECTION REVEALED NO FIRE WAS PRESENT. TECH FOUND SOME DISCREPANCIES. FIREWALL APU MOUNTS NOT SEALED CORRECTLY. HE IS STILL LOOKING THE APU OVER AND WILL MAKE NECESSARY REPAIRS AS HE PROGRESSES. (TC# 20190723003)