Why won't the AC in my truck blow cold air?

I have a 2002 Ford F-150 and all summer long the AC has failed to blow cold air. In fact, over the last couple of days, the air that does come out seems to be getting hotter. It's not the coolant for sure. What else can I do to fix it? Should I just take it to a shop for repairs? I live in a state that gets hot in the summer time so it's an understatement when I say I need my AC to blow cold air.

If the drive belt is ok, the pump unit could be faulty, if its not a coolant leak. Whatever the fault, though, you'll need to take it to an aircon repair shop to get it sorted out…

In such an old truck many issues first charge the system. If it works for a few days or weeks then quits you have a leak. In the worst case you have a blown compressor.

Hi this is a case of wear and age in most cases. Air conditioning systems on cars usually have issues with the matrix heat exchanger over a number of years buried deep within the heater and dashboard of most cars this matrix itself gets a leak.
this means that the matrix needs to be replaced this is usually an very expensive job costing more in labour charges than the car is worth to replace the unit.
re-gassing the system sometimes works as these systems lose integrity over time.
the refrigerant gas leaks out. Due to age and rotting of the various joints in the system.
so pipework may also need to be replaced as well as the heat exchanger so this could turn out to be a very expensive problem to fix.