Hot air blows out wen ac is switched on how do i re fill ac unitif that is the problemb

An AC system blowing hot air is usually due to a low freon charge or a non operational AC compressor. If the fuse blows, disconnect the compressor electrical plug and turn on the AC. If the fuse doesn't blow, suspect a compressor problem. If the fuse continues to blow with the compressor disconnected, there is a direct short between the ON/OFF switch and the compressor which can take hours to diagnose

check the freon charge for the a/c system to low can shut off the cutch

charge the a/c add a/c dye and ck. for leaks

you say it will blow cold and hot air for only a few minutes. You don't say but I assume you mean will blow cold a few min. when turned on AC max , blow hot only a few min. when turned to heater hot. Assuming thats the situation and you say AC charged and shows good on the low side -you should charge the AC to a full charge on the low side will cause problems with the AC air compressor kicking on and off. I suggest while the engine is running and turned to AC cold max watch the AC air compressor clutch to see if it does indeed kick on and off if so charge completely. As far as the heater make certain you coolant is all the way to the top and the best way to do this is when engine is completely cold remove radiator cap and fill completely and completely close cap then fill overflow container just to the cold level. That should fix your problem.

Make sure your coolig fan(s) are running while the ac is on. I''m not sure how you now that you have sufficient refrigerant in the system, but I would also have that checked. Over filled systems can act that way too! Last but not least, high and low pressure switches should be checked, amd if all else fails, check the expansion valve.

you have moisture in the system this causes your expancion valve to freeze up an stop working, thats why it works for sort time and when it de-freezes stars working again. you need to do a EVAC & RECHARGE with a good AC service equipment, specially attention to pull vacumm por at least 20minutes so you get all moisture out of the system.
Good luck

u should first evacuate ur system down to vacuum bfore adding freon. chances are system is full of air,therefore not allowing full charge to enter ac system. also make sure ur clutch is engaging at the compressor, u can see wen its on and wen its off.

you may have over filled the ac with reon and are over pressuring the system causing the high pressure switch to activate shutting off the ac, each can is 1lb

The air conditioning system need to be fill with gas,there is not enough gas in it that why it is doing that,Hope that help you,If there is not enough gas ,when you switch on the ac button it turns the ac compressor and cut off immediately because there is not enough gas.

HI WHAT YOU NED TO DO IS MAKE SORE THE COMPRESSOR IS RUNING WEN YOU TURN THE AC ON IF DOESN'T ENGAGE THE MEANS THE AC IS LOW IN REFRIGERANT