Just a few Air Conditioning System Maintenance Tips
These easy to understand HVAC maintenance tips are for common tasks that almost any homeowner can perform.
Please do not perform these tips if you are not comfortable performing them. Electricity is dangerous and can cause serious injury or death, always assume electrical power is on unless you have checked it with an appropriate electrical meter. Ameri-Serv, Inc. assumes no liability for the use of the information provided on this website. Before beginning please read the following article. Understanding Electrical Circuits and Standard Household Voltages
Things you can do to maintain your air conditioning system
You can keep the outdoor air conditioner clean. You can vacuum out the inside of the unit and get all those leaves and stuff out. On most units you can gain access through the service panel. Be sure the power is off before opening the panel. Be careful not to knock off any wires and do not hit the coil as you will cause permanent damage.

Dirty
Air Conditioner Condenser Coil. Next, after you close the access panel and secure it with the screws and with the power still off, you can rinse off the condenser coil with the garden hose. Never use any chemicals or cleaners on your coil, always allow a trained technician clean your coil if it requires a chemical cleaning. Granted, this should be done every year at a minimum, if you condenser coil has never been cleaned then it is strongly recommended that you have a qualified technician come and clean your condenser coil with an appropriate chemical. After it is clean if you rinse it every year and get the dust out your coil should stay in great condition.
Always trim any bushes or trees around your condensing unit as part of your
air conditioning maintenance routine (outdoor air conditioning unit) and maintain a couple feet of clearance all around the unit. Most importantly keep any male dogs away from your air conditioner as the male dog has a tendency to make a mess of your air conditioning and can cause permanent damage.

You can also keep the indoor coil clean if it is easily accessible, many are not easy to get to so you should have this cleaned by a professional. Never use any chemicals or cleaners on your coil, always allow a trained technician clean your coil if it requires a chemical cleaning. You use fresh water and rinse the coil if you can get to it, same idea is to rinse the coil clean every year at a minimum.
A couple last things to note is to check your condensate drain pans and keep them clean as well, any mold or other growth should be killed using a 10:1 solution of bleach, 10 parts water to one part bleach as the strongest solution. Spray and clean and rinse with fresh water.
Also check your condensate drain lines to make sure they are clean and flow water without backing up. All condensate drain lines should also have a trap and these sometimes will build up dirt and debris and require cleaning or replacing.
Always be very careful not to touch your coils, damage can result on many model types. To remove debris from the coil use the spray of the fresh water, if the debris does not come off call for a qualified technician.