More often then not the AC will only blow hot air. At times it will work for greatlong periods of time and other times it work barely at all. I have noticed no distinct pattern in this issue. The issue can arrise several times while driving. When it is operating it works great so I don't believe its a charge issue. I believe the culprit to be an electrical issue. I have changed the AC compressor relay with no change in symptoms. Any idea where I should start troubleshooting?

 

I would first starrt by pulling the two heater hoses going to your firewall and putting a splicing the two ends together. This will eliminate your heater for now. See what happens

 

Nice idea, However I don't think this is the issue as I have checked the compressor during one of these episodes and the A/C clutch isn't engaged.

 

I would still check the refrigerant charge. You may be just at the point where the low pressure switch won't engage the compressor. Sometimes it may because of differences in outdoor temps and everything will seem fine for a while.