how to know when air conditioning needs freon. the clutch cycles on and off
on 2008 Kia Spectra

how can i let pressure off the system low pressure side

Asked by for the 2008 Kia Spectra
The use of a a/c gauge is the way to determine if the a/c needs Freon, this can be something else going on such as a pressure switch or electrical condition such as the a/c relay or even the a/c clutch. And beside it is illegal to vent Freon in the atmosphere.