There is no such thing as Air Conditioning coolant.
You can try to repair your car air conditioner at home by adding coolant or flushing the coolant system. If that doesn't work, it could be a more complex problem with the car's electrical system and unless you are a mechanic, you should probably take it to someone who is to avoid more damage.
No.
It strains any impurities from the coolant.
Any air conditioning service person, it is a large part of the job.Believe it or not I find locating them more difficult most times than fixing them.
Your description sounds like engine coolant to me.
R134a
R134a
Originally this car had R12 refrigerant. It may have since been updated to accept R134a. The coolant/radiator system is not part of the air conditioning system. But the hot antifreeze-coolant is used for the heating system...
r-134A
Very toxic. Do not inhale, it deplets the oxygen.
You may need to charge your a/c with coolant.