Fucuk Daikin.
Beli 3 rosak 2.
Fucuk!

By the way, yesterday I bought AC spray at Mr Diy, opened up all AC at my kampung house, sprayed this liquid to the coil and blower, and cleaned the filter net with foam b4 install back all together.
All noted massive cooling feedback than previously, as I noted too many dust, collected at the blower area.

Other way around, u can spray it using hand spray. The water u spray will flow through the drain pipe below the coil.
Using chemical will "eating" the dust hence it look much cleaner.

This one bs. Only spray once maybe, but spray regularly there's really not much need to call for service. The spray will become watery and bring the dirt to the drain pipe, with the condensation over time will help also.

Most important thing is blower, when it is dusty then you feel air weak. Shortcut is spray foam directly on blower but like that very messy. Learn to take apart and wash blower is better, more work but not difficult. Once a year enough, even less if you use air purifier regularly.

Yes it is recommended to use those canvas.

Once you get the cleaning canvas, you can use water gun or home water hose, to spray the blower drum to clean, hence you dont need to remove the drum. Some AC, its very difficult to remove, takes a longer time and need to be careful not to break plastic holders or the motor holders. Water gun makes life easier. Or next time when you purchase a new AC, do get those that can easily DIY models, like midea, hisense, etc