Bring down the AC. Remove front panel using screw driver. Cover the compressor electrical connections and blower machinery with plastic shopping bag.
Add a bit of surf excel in bowl of water.
Wash the whole AC with low pressure water. Apply surf and water mixture with sponge on parts needed cleaning.
Clean the front panel with surf and than apply a bit sewing machine oil on a cloth and polish it.
Dry it using ceiling fan.
Install it. And run it after 1 hour.