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Energy Saver: Air Conditioning
(continued ...) loosen chunks of debris that are stuck on the intake side of the coil. Not aligning the water stream with the fins could bend them. Read bent fins as bad.
The next method is much more difficult but most effective and my preferred method. This will likely void your warranty but since it was probably only one year long and assuming this is at least the second season, it doesn't really matter.
Again, if there is no local power disconnect and if you are not absolutely sure that you have power switched off, do not proceed with the next steps.
Get an old coffee can, screw driver or nut driver. Dismantle the coil shields, weather covers and top cover. Carefully remove the least amount of screws needed to remove the top and side weather guards. Place screws and clamps in your coffee can. If your memory is bad, use masking tape to label where things go. Keep dismantling until you can see inside where the compressor sits and particularly the inside of the condenser coil. Follow the previous steps with vacuuming and paint brush dusting. But now you have access to both sides of the coil. Vacuum and paint brush dust both sides. Vacuum the bottom of the unit around the compressor. Then, gently wet both sides of the coil with water from the hose and carefully get water in between all the fins. Primarily spray water from the inside out (opposite to the normal air flow). This reverse flow alone will dislodge bugs and guck. Spray at up and down angles but parallel to fins. Now apply the orange based cleaner from the outside first and then from the inside. Try to get the cleaner deep between all the fins. You should be using nearly an entire can of cleaner. Let cleaner set for 5 to 10 minutes. Do not let the cleaner dry on the coil fins. Next, rinse ...