What was found
FLT 87 JFK-SLC, AIR TURNBACK TO JFK DUE TO CABIN AIR REACHED TOTAL TEMPERATURE OF 144 DEG CENTIGRADE OUTPUT. NO HOT AIR FAULT ON ECAM. TURNING OFF HOT AIR VALVE INITIALLY HAD NO EFFECT, HAPPENED TWICE. ACCOMPLISHED TSM 21-63-00-810-846. INSPECTION OF DOWNSTREAM CHECK VALVES AND BELLOWS BETWEEN PACK OUTLET & MIXER WITH NO FAULT FOUND. DUE TO HOT AIR P/B/S HAVING NO EFFECT ON CONTROL, REMOVED & REPLACED PACK 1 & 2 TEMP CONTROLLERS IAW AMM 21-61-34-04. OPS OK. 27HH TEMP CONTROLLER P/N 759D0000-02 S/N 2810.