Fill and Check Airconditioning AC Coolant

Fill AC Refrigrant (FREON) - AC System malfunctions and even completely shuts down if the Refrigerant pressure is low or if it is high. If the pressure is high ,the ac may shut down usually in the summer days, when the outside temperature is quite high. So when the AC starts blowing warm air, you know that it is time to check the freon pressure . Ofcourse the assumption here is that the all else is fine :- AC Belt , The AC compressor itself , and the hoses and pipes have now leak and sensors are ok.

To Fill the refrigerant , you need a can of the recommended refrigerant(freon) and pressure hose to fill it up. Wally and most discount parts store carry these. Some times they sell a can with attached hose and AC pressure gage on it as well , that is usually re-usable and cost about $25  or so. Lift the hood of the car and identify the High and Low pressure AC Lines. These are aluminum in color Both lines have intake ports. These ports have plastic caps that are marked with the letter H and L in most cars. ALWAYS fill on the Low side. Take the cap off the cold port. Now start the car and put the AC to max cold settings and open all the vents. Shake the freon can vigorously for 1 minute. Now attach the hose to the Low pressure port and check the pressure, and open the valve slowly, Keep shaking the AC can.AC Refrigerant should flow inside and you can observe the can getting lighter and lighter. The gage will tell you that it is full when it comes to around 30-35 psi point of the (blue part) gage on the dial. At this point you can shut of the valve and remove the hose from the cold port. If the Gage stays further on yellow or red , it can suggest an underlying mechanical or other issue and it it needs professional repair. Once this is done you will feel the air more colder. Please put the AC Hose,gage and Can away in  safe place , preferably in a plastic sealed bag.

In certain situations even filling coolant will not help. This means that moisture has entered the system. This moisture need to be be vacuumed (sucked) out, using special vacuum pump. But this would also suggest that there is a leak in the AC system. Leaks are usually found out by throwing soap water around the hoses to see if bubbles are formed. Leaks can also be found using Ultraviolet fluid. So first leak has to be fixed before vacuuming the AC and adding new freon. Some basic understanding will heavily decease the cost of professional repair and avoid anyone from ripping you. What is being said is , if there is simple leak ,at a joint and the AC repair shop wants to change the compressor and all pipes, then they are ripping you off. See what I am trying to say here.