My ac was just filled it worked for awhile now it's blowing hot air ,there isn't a leak i checked ty

if the compressor comes on and fans work when the ac is on ur compressor and fans work , if u fill the a.c and it fails to hold pressure you obvosuly have a leak look around to see if the condensor is black with oil spots look at your ac lines for oily sports especially were they made the crimps . alot of a c orings go bad , after u visully check for leaks and cant find anything fill the system with nitrogen and spray soap and water if that doesnt help put a die in it and re fill a .c keep and eye on ur a,c and u will see the stain of dye of ur a,c compenet , make shure to were those a c goggles, if u see a.c stain on the drain tube ur evap is leaking good luck

The question is: why isn't the compressor clutch turning

The compressor isn't likely seized,it may leak refrigerant,
but won't be what your asking.

The clutch can be jumped to test that

If okey, then you have to diagnose the entire
A/C Electrical System

How do you know it is properly charged,you put
refrigerant gauges on the system?

take it to an accredited ac specialist shop and have it checked for leaks
sound like it was gassed up to sell it and after you got it the gas has leaked out

check your blower motor under the passenger side of the dash, round plastic box three screws pull it out something might have fallen though your cowl and chewed up the fan blades. as for the ac your r-12 is probly empty or has a leak bring it to a local garage and have them flush and fill your cooling system. heater would be your thermostat not openig properly, by far your cheapest fix under ten dollar part.

check for leaks

Check the evaporator coil by sniffing the vents,floor is best, with your tester.

must likely you have a leak somewhere in your ac unit you must take it to a ac specialist and have him check for freon leak

Most probably you have a leak some where.
What you can do is have it checked proffessionally , or if you like to do it your self :
Pressure fill the AC with AIR and you can use any air pump that will fit the lines. After filling the air (up to 300, not more han that) you can get some water with soap , and put soap over the AC lines and seals and corners in the engine compartment. if any leak you will see soap bubles. If nothing shows there then you have a problem with the cooling tank , radiator inside the dash and you need to check that.

hello,good day,seems your recirculating pump need tobe check,ty

fill your ac up agian if you dont know how go to any auto repair shop to fill it up it will cost about 60 to 80 dollars