TC changed end and reported heavy condensation at one of the saloon cars while changing end. Staff ( KTB) checked and confirmed Front M1 car A4 door, air-con con densation with minor drips. ~~~~~ TC changed end and reported heavy condensation at one of the saloon cars while changing end. Staff (KTB) checked and confirmed Front M1 1678 car A4 door, air-con condensation with minor drips. Checked -OK.No condensation found.Change 1678 AC Filters with thicker filters.09/06/20 U(D).