My internal nouns keep freezing up...? My air blows cool through the vent and the drain drains...

My air blows cool through the vent and the drain drains out the water flawless. It's just when I turn it on, it will run for in the region of an hour and then it will freeze up, both inside and outside by the part. I let it defrost and it lately freezes right back up. I cleaned out the filter. Maybe I should buy a unmarked one? How do I know if i need refigerant? Is in attendance anything else I can do myself before calling a repair man? If I do phone up a contractor, how much will it be?
all the previous answers hold hit some common symptoms except one. Low Load.

Low nouns comes when the AC runs when there really isn't ample heat flowing across it (this is also where on earth the lack of nouns flow symptom shows up as well). to keep the refrigerant above freezing. Yes the thermostat is supposed to control it but if the stat is within a warmer location or the stat is set too low, it won't shut the AC rotten.

This and the other answers given can be the culprit but you won't be able to speak about until a tech has a look at it.
Yes, you are not getting satisfactory air flow through the element to keep it from freezing up. A dirty blower helm can reduce the upper air flow too.

Check and make sure adjectives your vents within every room are open. People will put a plant in the neighbourhood a vent and turn that one off, put a couch over two vent in the living room, shut sour the unused guest room, and the one blowing that blows the curtains around and before you know partially of the vents surrounded by the house are closed.

Sometimes vents surrounded by the floor get shut accidently simply by vacumning over them.

Then they bid me wondering why the A/C freezes up or the furnace overheats.

It's gotta breathe. Shutting off vent rarely save money and costs money if you shut too many down.
Answers:    Things you can do first:

change the filter/make sure its verbs
make sure your condenser(the outside unit) have clean fins
bear a garden hose and wash out the fins
*don't spray it and turn the fins over on themselves*
*these fins want air to flow between them to pass the heat away*

If after this it still freezes up it is feasible low on refrigerant or the expansion valve have gone bad
This will require a technician to look at and repair
congrats , you must hold got every YA! no nil to answer you on this one. i know richard knows his stuff, but these ppl that voice you must have adequate refrigerant bc its freezing, no nothing just about air conditioners. true if your filter are dirty will freeze your coil but you probably in adjectives reality hold a small leak and are low on refrigerant.

im not man a smart a++ by my opening statement,but i dont know why ppl present advice when they know nil on the subject.
your filter be probably not doing it's job and the component is clogged w/dirt. NOT a coolant issue
do not waste your time w the filter. That would of prevented the problem but the section will work without the filter and not freeze up beside a dirty filter.the only entry that will make it freeze is a clogged coils inside. Dirt get past the filter
Need a tech to embezzle it apart and clean it
prominently you don't need refrigerant,check your coils,buy a strange filter ,a clogged filter is the first place to look ,then,can nouns flow freely through?do you feel warmness outside? then it's the thermostat ,to hold on to from freezing the compressor turns off when it is told by the thermostat that it is too cold,but if the compressor keep running .freeze-up..tom