My AC unit wont blow the cold air.

you will need a thermometer, you can use a meat therm.take a temp reading of the air going into the return and then coming out of the supply at the unit, it should be at least 15 to 20 degrees cooler in the supply, if not it may be low on refrigerant also check filter and return duct make sure your not pulling air from attic

i can help u but mikep858 i need u to give me the model of this ac okay the correct one

best regards

It sounds like the compressor is not coming on in the outside unit. If it worked fine and was cooling before, then your compressor probably over-heated and tripped the internal overload switch which causes it to stay off while everything else is working. The most common cause of your compressor over heating is an incorrect refrigerant charge, though it could be a few other things like a restriction in the copper line set. You will be able to hear the fan motor and the compressor kick on if you listen close while the system first turns on. If the compressor is over-heated, then after it cools to a save temperature, it will come on again, but only till it over-heats again. I would have the charge checked on the system, but remember that if the compressor is over-heated when the technician gets there, there is nothing he can do until it cools down and time is money! It's best to not run it until the problem gets figured out. Hope this helps and points you in the right direction. Good luck!

If it does not have a furnace or heating elements for heating, then it is a heat pump, which is rare for a central AC system, but makes sense of the fact that it blows warm air when you reset the pressure switch, which may indicates freon pressure charge problem if your AC system has a reverse valve and uses freon to for heating (heat Pump).

Do you get heating when outside unit runs? if you do, check freon pressure levels and top up to required pressures. The button you depress is a pressure reset switch ... that is if your AC system is a heat pump ... which, as pointed above, it is not common for central ACs.

This could be complicated to resolve over the internet but I'll give it a try. When you stated that it stoped blowing cold air, did it stop blowing air all together? Also is the outside unit rtunning?

Check outside unit if unit and compressor are running feel the large line to see if it is cold. If compressor is running and line is not cold possible charge problems. You may have a capacitor problem outside. they go out quite often. You can change this yourself, Open up outside unit and the cap is the silver bullet with terminals out the top. Bad cap can cause compressor to not operate and also the fan. You need to clean the coil inside or at leat check the coil to see if it is clean. You can clean theis with a toilet brush do not go against the coil bit brush with the fins. You may need to call a service tech but try these options first. russ

You need to have a pressure gauge the reads for R-22. (Freon) It sounds like the system might have a leak. Look for a wet place any place on the units pipe system. It has a little oil in with the freon that is forced out of any leak. If you see a wet place this is oil. It is also the location of your leak.

I have some things for you to check. If you look at the outside unit the lines going into the house. Are they frozen? Have you had any yard work done, the reason I ask is they could have accidentally cut or pulled out the thermostat wires to the ac unit. Also, inside check for the same thing, frozen lines. Also, you may want to check the drain coming from the inside unit, it may be clogged.

The thermostat is the controller.

You have done a good job under the circumstances. It could be a bad start/run capacitor as well. It carries a lot of amperage so I suggest hiring a technician to check the capacitor and the motor.