20c setting is very cool. If you still don't feel the cool, either your AC under capacity or cool air leaking.

Get a room thermometer and check the actual temperature. How much different between your setting.

I am using panasonic inverter:
http://www.panasonic.com/my/consumer/home-.../cs-s13pkh.html

http://www.panasonic.com/my/consumer/home-.../cs-s24pkh.html

Start giving me "tak tak tak" sounds after 7 months using it even the swing i fix it static and no move (looks like the sound doesn't come from the swing).
anyone with this model got this problem?

I don't know how to take off the panasonic split unit or compressor unit.
So i use chemical to wash 3 areas with plastic cover at bottom:
1. Aluminium mesh (spray on the mesh)
2. The split unit fans (spray from bottom towards the fans)
3. Compressor mesh (spray on the mesh)

My wife did feel that it helps a lot.
1. Faster to cold down the room
2. Cooler
3. Stronger wind (previously too much of dust block the split unit fans)

Temporary i do that 3 steps above until end of the year i only ask professional people to service the aircon.
For that outdoor compressor unit, do you guys think it is OK if i spray water on the mesh without turning ON the fans, do you think it will spoil the fans or the compressor unit??

The panasonic aircon price already up almost 15-20% compare to last year.
ur price exclude installation?

If possible try to get econavi feature,
I noticed that the econavi help me save lot of money on my tnb bill.
it will auto adjust the temperature celcius when no ppl inside the room (eg: u on aircon but u went to kitchen or bathroom for a while), and as well as when you are sleeping (no movement).

17x10 ft room i ON the 2.0HP inverter aircon 11PM->7AM 25C speed 3/5, only use up to 4KW of electricity for this period (include other stuff like 600L inverter fridge, 24/7 water boiler, autogate / alarm system / 3 cctv and about 40W lighting.

Yes. Econavi still can adjust the split unit fan speed and swing top and bottom also can adjust.
the only thg you can't adjust is the left-right swing. The econavi will adjust temperature +2 automatically based on situation.