4 aircon? If your electric meter is 15 amp then you multiply 15 with 220 volt -it gives max 3.300 Watt that is what your system can take at the same time. A fuse will normally be 10 amp (2.200 watt) for one fuse. If each aircon use about 1000 watt. then you have a problem. You can not run all 4 at the same time because your installation with a 15 amp meter is too small.
You can of course change your meter to 35 amp (35x220 - 7.700 Watt) Warning. wire size is important here, your present wiring might not be sufficient, talk to an electrician.