for pressure washing, this guy use plastic bag and screw driver to fill in all the gap. i see many video, no one really try to seal up the pcb area like him 8.20sec onwards after washing he also wipe dry even if using plastic bag for condenser if you put chemical you need to spray downward and explain why

just did my first diy cleaning, my AC look clean but after spraying with ajax then wait 6min then spray 2nd time, and pressure wash the fin and blower, my FCU dont look dirty le (blower hardly any dirt, and fcu no dust stuck on it) but after washing i can feel it even colder then before before washing   after washing    

i think i will share when i got info on ac cleaning     add some video to help better understand. why cant/unable as quote It's just a strip of plastic about 1cm deep. , I use finger to dig through the scum,  spraying water on the blower, all the dirt went upwards and stick everywhere inside, and cause this problem.             the back drain tray is below back coil, so doing water spray might not be able to reach but can try to pressure wash by spray water upward and downward after cleaning it done, of course best is to remove blower (but i dont know how) so next time i wash i will try this   https://i.imgur.com/JEOQlLw.mp4 https:// imgur.com/ JEOQlLw     https://i.imgur.com/v3zCm86.mp4 https:// imgur.com/ v3zCm86         if remove blower of course can pressure wash it as it will shif the coil just enough to pressure wash the back tray https://i.imgur.com/JbZmGHQ.mp4 https:// imgur.com/ JbZmGHQ       if want more simply AC to diy clean then choose midea         some say midea is lousy some say good, i dont know, but their diy cleaning for me it the easiest https://youtu.be/20heqJcxx9E