I have 2 air con units in a 74sqm condo. The one in the lounge appears to be dying in this hotter weather we are having. They are 7 years old.

The fuse switch has always tripped after I came back from a few days away and fired the A/c but thats not the problem.

In the last few weeks when the air is running during the day I hear a "zapping" noise followed by the air going warm. Usually turning it off for a while gets it cool again.

what should i do to fix it?

Get them serviced perhaps?

Get them serviced. The zapping noise could be ice forming then hitting the fan.

Already booked. 900bht a unit for gas and a clean. Thats all I know as the GF organised it