EMISSION CONTROL SYSTEMS — Dash Pot (DP) System EC-11 INSPECTION OF VTV (Black) VTV Filter EC-3433 1. CHECK AND CLEAN FILTER ON VTV (a) Check the filter for contamination or damage. (b) Using compressed air, clean the filter. (Black) Air (Black) Air EC-0151 2. CHECK VTV BY BLOWING AIR INTO EACH SIDE (a) Check that air flows without resistance from B to A. (b) Check that air flows with difficulty from A to B.