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.
A complex machine such as an air conditioner can fail in many different ways, but the most usual way is a leak of the coolant (which is probably freon).
7 pounds
There is no such thing as Air Conditioning coolant.
Never, unless you have a leak.
Wet passenger flood is caused by either a leak in the air conditioning drain line or a leak in the windshield sealant or a coolant leak coming from the heater core.
No, a radiator does not contain freon, as freon is a refrigerant used in air conditioning systems, not in vehicle cooling systems. Radiators typically use coolant or antifreeze to regulate engine temperature. If there is a leak in a vehicle's cooling system, it would involve coolant rather than freon. However, if you are experiencing issues with your air conditioning system, it may indicate a freon leak in that specific system instead.
Gravity, it is tilted the wrong way.
Whether the leak is miniscule or not is not the issue. If your system is leaking refrigerant, you must have it repaired. Any technician that puts refrigerant in a leaking system and does not identify the leak is not worth keeping. Answer is, since it is a sealed system, if the unit is losing coolant there is a problem, there is a leak. However, as a practical matter and since the leak may be miniscule, having your system checked every couple of years is not a bad idea.
No.
a leak
No, unless you have a refrigerant leak.
It strains any impurities from the coolant.