I would like to think the compressor is like the heart of the airconditioning system. It circulates the hot and cold air to keep the room cold.
So when it is spoiled.. what do you do?
It is not cheap to do a 'heart' operation - it can easily cost SGD1000 or more, depending on the brand, model and system of your AC.
So how do you decide?
First you got to be sure it is a compressor system. The findings of the technician is likened to a doctor's diagnosis - you may want to seek a 2nd (or even 3rd!) opinion or asked for a well qualified technician to confirm the evaluation. So to be sure that the compressor is the problem and not something else. You won't be too happy to know that you have spent thousands for a wrong diagnosis.
So once you have confirmed it is the compressor issue, is it still under warranty? Usually compressor are under warranty for a few good years. Check your receipt / guarantee card.
And sometimes, you can change only the compressor, though you may want to consider changing the full outdoor unit (ie the condenser unit). You would want to have the expert's advice. And what about the cost of changing just the compressor vs the whole outdoor unit?
Then with all the cost in, you may also want to consider changing the wall mounted units as well - this will be a full AC replacement. First the cost might not differ than much between just changing the outdoor unit vs changing the full AC system. 2ndly the compressor may not operate at a optimized level with a different AC unit it was created for. This will affect the efficiency and the performance of the whole AC as a system.
So all in all, you may want to compare the costs after getting a full diagnosis from a well qualified technician. This is not an easy decision to make, but with the steps above, hopefully we have been of help!