Why don't you just call a specialist to solve the problem with the air conditioner? Besides, you say that this is not your strong point. You're just wasting your time solving a problem that you don't know how to solve anyway. The reason for the malfunction of the air conditioner can be absolutely unpredictable trifles. I also do not understand air conditioners from the word at all. When I buy a new air conditioner, I just buy the service with the air conditioner. In case of any problem, I can just call, and specialists will arrive in a few hours and do everything necessary.
___________________________
https://www.socool.sg/pricing/