how to add freon
first you need the correct equipment for that. let say you have it!!! the correct way is to connect the high and low pressure hoses to check the pressures of both and if needed (with the A/C turned on) connect the freon canister and add freon the low pressure should be somewhere between 30 and 40psi and the high depends on the vehicle between 150 and 230psi i recommend to vacuum the system if to much freon is needed and make a pressure test of the system for leaks.
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