What was found
WHEN TURNING APU BLEEDS ON, YOU GET A STRONG DIRTY SOCK SMELL FROM THE AIR. IT DISSIPATED WHEN USING ENGINE BLEEDS BUT CAME BACK ONCE WE WENT BACK TO APU BLEEDS. IT IS STRONGER ON THE GROUND VS INFLIGHT. CORRECTIVE ACTION: REMOVED BOTH L/H AND R/H FILTER SOCKS. NOTED BOTH SOCKS CONTAMINATED AND DISCOLORED. POO JWB 5-13-26 IAW MM 21-51-13-000-801. INSTALLED NEW FILTER WATER COALESCER SOCKS IAW MM 21-51-13-400-801. PERFORMED A LEAK TEST OF THE AIR CONDITIONING SYSTEM IAW MM 21-51-00-790-801. NO LEAKS NOTED. RAN APU AND ENGINES BLEEDS SEPARATELY, CONFIRMED NO ODORS NOTED .