A/C - Compressor Noise After Start-Up

SOURCE: Kia Technician Times

TITLE: A/C Compressor Noise After Start Up

APPLIES TO: All models

SERVICE TIP:

A/C compressors may make a "clunking" sound when they are first engaged, especially after extended periods of non-operation. Although varying in sound level and intensity, the noise is characteristic and inherent in the design and construction of both the compressor and the A/C system. During standstill, a small amount of refrigerant may collect (in liquid form) in the compressor, and the displacement of this liquid causes the noise during initial operation. As soon as the compressor has dispersed this liquid (within seconds) operation returns to normal and the noise disappears.

Provided the A/C system is charged with the proper amount of R134A, and no other performance concerns exist, the "start up" noise described above does not warrant A/C system repair or replacement of the compressor.