wo16331 PROBLEM: WHEN UNIT IS TURNED OFF IN HEATING OR COOLING, OUTSIDE UNIT MAKES UNUSUAL NOISE. DIAGNOSIS: UNIT WAS INSPECTED AND WAS FOUND TO HAVE A LOW CHARGE. AFTER FURTHER INSPECTION OF THE INSIDE COIL, A LEAK WAS FOUND ON THE COIL. WEATHER MASTERS RECOMMENDS REPLACEMENT OF THE INSIDE COIL TO INSURE THE SYSTEM DOES NOT MALFUNCTION DUE TO LOW CHARGE.