MY AC blows hot, it wont take a charge. a shop told me it needs a compressor so put on a new one and still won't take a charge and blows hot air

hey they all work great new, but not now, the endless story.

no car told no year told no model card told (fun?)
hot air is actually outdoor air? that is 100F here. USA?>
as you do know the HVAC on cars can in fact fail and stick in heater mode.(damper failures)
rules of the game AC. (short list I have huge list, ask as we do tests)
1: the dampers must work correctly in the heater box.
2: the compressor must spin (and does)
3: the refrigerant must not be over charged, ever or it will fail.
ample is not the correct word, the correct words are
the Refrigerant it put in by weight. (an exact measure ask any HVAC shop and hear those words)

5: engine over heat sensor shuts down AC. (not this case)
compressor spins, so. no this.
6:blower is dead, in AC mode( not this case it blows)

7: the condenser fan up front is dead, fails parked but AC works great at highway speeds. 50mph (+)

on my car the ac/heater has self test mode, to be sure all damper motors work correctly so we do that first. (mine is JEEP)
most modern cars have 3 dampers, hot cold and recirculate.
use recirc mode for AC for best cooling.
some AC have hidden in dash filter that packs up in lint and can not pass air now.

on one car a rodent got into the fresh air vent and went deep into the heater box nest built, but was in front of AC evap core but blocked cold air from evap core. ( what a shock)

why not take it to any ASE shop and as for diagnosis.
pay the man to do al tests on AC
and if you over filled it , bingo you caused it.
the modern R134a , hates overfilled. !! repeat for effect.

Are you measuring from the Low side with the AC ON? Because you need to do that. (and out door temp tables read that)
the factory service manual tells what it must be.
and no 2 cars are the same due to volume the same.
classic case of fail. (sad story time)
R134a leaks out, (so many ways on cars)
and owner buys the $12 Walmart kit and overfills. it. and fails.
or worst case 2:
if pressure was zero , key off and on. the loop now has water inside the loop (called humid air) and that makes it bad after a refill.
the water is the killerr here.! must be vacuum pumped down first this case.
why not get it serviced by pros.
they do a full leak test with dye. do it now.

Only way to tell if A/C Evaporator Core Orifice tube is plugged is by looking at A/C gauge readings , An if it is plugged you more then likely need a new compressor , they become plugged with metal particles from worn out compressor. Your best bet would be to take your vehicle to a qualified repair shop .

If you have climate control it could be the main processor. Something could be shorting the blower relay to keep it on. You would also need to check and see if the system is still full of freon.

start off with the cheap possibilities and make your way threw.
I'd start off with replacing Air Charge temperature sensor, make sure your AC Hose isnt leaking anywhere, if those dont solve it then replace ur AC clutch, last chance would be replacing AC compressor. sometimes the compressor will malfunction randomly. or the AC clutch might malfunction aswell. covering these steps somewhere along the line you will have working AC again! good luck

Sort of.
If the system is empty, you would need to jumper the low pressure switch to power the ac clutch to put the first can or two of freon in.
Keep in mind the system is supposed to be vacuumed out before adding freon, so if it is full of air you won't be able to put the full amount of gas in.

I'm sorry you have had such bad experiences with the shops.
I would have stopped at the second one and forced them to fix it at their cost.
I doubt you will be able to find the problem yourself, but I understand your hesitation to go back to another mechanic.
I will be happy to try to walk you thru the diagnostic process but it may take a few days.
First, do you know if the system is full of freon ?
If it is full, do you know if the compressor is running when the ac is switched on ?
The first shop should have discovered the blown fuse once they charged the system unless it took a day or two for the fuse to blow. The second shop that put the compressor on should have found the faulty fan, and the leaking hose if it is in fact leaking.
So should have the third shop.
If the compressor was faulty, and the system had been empty for a time, the hose could have started leaking once the system was being used. The pressure on the high side is over 200psi when the compressor is running.
Let me know where you want to start with the diagnosis after you answer my questions.

The leaking heater core won't keep the compressor from working.
You say the ac system is charged, but the compressor won't come on ??
The compressor has to run to charge the system, otherwise you will only get half a can of freon to go in. The system holds 3 or 4 cans when empty.
The low pressure switch has to be jumped to make the compressor run to take the first two cans of freon.

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?

Why do they want to replace the compressor?noisy?If you can put a charge on the ac then it's hot again after a day,then you have a leak.all the ac lines have o-rings where they are connected.without put dye in the system you wont know for sure.So I would try that first.

CYCLING COMPRESSOR COULD MEAN TOO MUCH OR TOO LITTLE FREON.TAKE IT TO AN A/C SHOP