Now that the cottonwood season is almost over you should clean the outside fins of your air conditioner condenser, this will help your air conditioner to function better. Most cleaning involves just spraying the outside of the condenser unit(the outside part) with water using a slow side to side motion and starting at the top and working your way down, kind of like spray washing a car. I have used a shop vac also, just be sure not to damage the fins. You should clean it every thirty days or so during the summer and give it a good cleaning in the spring.
Be sure to insulate the refrigerant return pipes (the big pipe) and clean your condenser (just like a radiator) fins. Check my web site for other tips. www.homeinspectpros.com (Dogs may damage your condenser.)