What should i do to repair my ac on 1995 ford aerostar. should i shoot in some dye or just change compressor and get it recharged

You must remove the engine cooling fan (requires special tool) and the fan shroud, I have done about 100 of these and once those parts are removed it is easy to get at.

The most common cause for an AC blowing hot air is the system is low on refrigerant. A small leak will eventually lose refrigerant until the compressor eventually will shut down. Most compressors require a minimum of 20psi to engage and chill the air. Most certified service stations can diagnose and recharge most systems for $100-150 depending on where the leak is. There are do it yourself kits available at most auto parts stores that come complete with leak detector (R-134A with dye to show where leaks are) compressor oil, and a recharge hose.

check the compressor to see if it is clicking on/off then check make sure has freon then check ac compressor belt and shoot dye in the system use a uv light look for leaks

R-12 isn't designed to work in an vehicle so I have no idea what to tell you there. R-22 was used in vehicles but is not available to the general public without a license which cost more than the R-134 conversion kit.

Below is a guide to troubleshoot and check system function. This can be done by most folks.

Look at the front of the ac compressor and have someone turn on the ac from inside the car. The front of the pulley(clutch) will spin when turned on.

If it does not spin, the low pressure switch (LPS) is not satisfied. Meaning there is not enough freon in the system to operate the system. Means low freon capicity because of a leak.

The LPS can be jumpered to cause the compressor to run (clutch to engaged) which will draw the freon in the system.

The LPS is usually a two wire sensor on the suction of the compressor. (between evaporator and compressor) Unplug the sensor and install a jumper, this will engage the clutch. Connect a new can of freon
and fill to system capacity.

The capacity of the ac system will be on a label under the hood, do not overfill. Probably about 2 lbs. Local parts stores (Auto Zone and Advance) will have freon with stop leak. This may help the leak. They also make a freon with a UV dye. I always add a single can with dye so that if stop leak does not work I can find the leak in the future.

The system should be filled until suction pressure is about 30 to 38 psi..

Remember the flow for the a/c system is :
1. From the compressor a high pressure (HP) gas goes to the condenser in front of the radiator.
2. From the condenser a HP liquid goes to an expansion device (orifice tube or expansion valve)
3. From expansion device the low pressure gas enters the firewall to the evaporator.
4. From evaporator the low pressure liquid/gas mixture goes through the dryer back to the compressor suction.

It sounds like the compressor locked up. Do not attempt to drive the vehicle in this condition, you'll destroy the belt or just stall the engine and could find yourself walking to your next destination.

For a quick "fix", check to see if you can get a belt from a parts store that bypasses the AC. If that is available, it can keep you going until you get a chance to get it fully repaired, or just drive the vehicle without an AC indefinetly.

Otherwise, you likely need a new AC compressor and all of the components and labor that such a swap entails... which will not be cheap.

can you hear the compressor kicking on when you turn it on? If yes, the system may just need a recharge. Also they can iject dye into the system at the same time of charging to see if it has a leak.

Look at the front face of the compressor. Does the metal plate on the front of the pulley start and stop? If so, and you hear a lot of cycling (clicking on and off), you need to get your unit recharged. Good luck

You have a leak somewhere, possibly at the compressor or a pinhole in the condenser. An a/c leak detection kit can be bought relatively inexpensively at your local parts store, allowing you to inject dye into the system in the same process you would charge the system; an ultraviolet light (included in the kit) is used to see where the dye is leaking and pinpoint the leak for a proper repair.

have your ac system tested for leaks, i recommend to vacuum
and recharged with freon with red dye.

gl G