I have a central air conditioner unit that I have had for about 10 years. Recently it started freezing up. I changed the furnace filter. I have never cleaned the A coil. I opened the plenum and was hit by a lot more air from the fan then what I get out of my vents.
I have attached pictures to show what the A Coil looks like. I think it needs to be cleaned. I know I can buy cleaner at home depot that is self rinsing. I want to know if I use it, can it drip on the heating elements down below.

Looking up into bottom of coil. as you can see it is rather dirty.
https://www.dropbox.com/s/96ie0te2m38d5yi/20150714_162104.jpg?dl=0



Looking down to what is directly under coil
https://www.dropbox.com/s/t0vvr4r760...62550.jpg?dl=0

Top sides of coil
https://www.dropbox.com/s/ki2atitavu...62223.jpg?dl=0
https://www.dropbox.com/s/8bzru3b5gy...62127.jpg?dl=0

 

Can't open the pics but the spray cleaner will normally run down the coil surface and into the drain pan.
Geo

 

I was able to see the pictures, and the coil does look quite dirty. It's definitely worth trying to clean it.

 

I was over cautious, it stayed on coil just fine

 

That coil is definitely dirty and causing quite a restriction.
After the cleaning you should be getting a whole lot more airflow.

 

Before cleaning I noticed the line at the outside part that freezes having a lot of condensation on it. After cleaning it is dry. I don't feel as much air coming out of vents but I may be expecting more

 

You feel less air now than before you cleaned the coil ?

 

honestly I can't tell. I don't have a velocity meter so I can't measure and tell for sure. I may just be hot and tired.
Right now it is very humid in my house so I think it may take a bit for the moisture to be pulled out of the air before it really starts to cool it. We have the thermostat set to 76. It reads 82.

Like I said, I did notice no condensation on the line outside and the plenum feels cool to the touch so I am hoping all is well.

 

With that much "fuzz" I would have vacuumed it before using coil cleaner. You should also make sure the drain line from the pan is clear.

 

I sprayed the cleaner on it then shop vacced it. Then used the cleaner twice more on the bottom part. then rinsed it with clean water. Pan was draining clear water when I was done

 

I am stuck. I went to bed at 10 and everything was fine. I got up to check it at 12 and it was fine. I checked again at 2 and it was fine. I overslept and got up at 6. I was frozen. The temp in the house has gone from 85 to 76 but it took nearly 10 hours.

 

Did you say no condensation on the outside line ? The 2 outside lines go to the condenser should feel ice cold (large line) and warm(small line), if not, your Freon charge may be low.

 

Yes, I think my coolant is low. Or something worse. Either way it is outside my capabilities. I have a hvac person coming out tomorrow. Hopefully just need coolant.
About how often should it need coolant? Unit is at most 10 years old

 

Never need to add coolant if there is no leak. so let the AC tech check it out.