My house AC unit is blowing cold air but not much air is coming out of the vents. It will shut off and on at the thermostat. I believe from hearing some history that the coil can freeze up. Does this sound like the case and if it is, what can I do to fix it myself? Most importantly, what causes this problem to begin with? Thanks to all.

The first thing that you can do yourself is to check the filter, if it is the least bit dirty replace it.

Freezing over on the coil can be caused by several things, the most common is a dirty filter, but anything that reduces the air flow over the coil will cause it to freeze over.

About the only time it is not caused by low air flow is when your freon level is low.

If you find a dirty filter and change it, this might now solve you problem because as the filter gets dirty the dust, dirt, pet hair, dead skin cells will bypass the filter and go up to the coil and since the coil is moist from condensation it will stick to the coil and then cause the same results as a dirty filter.

Cleaning a coil is not an easy job, you have to take out screws and take the cover off the front of the coil and depending what kind of coil you have you may have to remove more screws and another plate to expose the bottom of the coil where the dirt and stuff will be.

If you need more information let me know and if my answer helped you please rate my answer.