Thats right, some of them have vacuum pumps but they only use it for bigger systems like 4ton+ or commercial installations. Main issue is that awam is not willing to pay extra for this job.
Also since they are not really parhay likhay so its hard for them to accept what they learnt from their ustad g who had 30+ years experience. Now purging would be okay few decades ago especially with older refrigerants but its all more important with R410, every AC user manual comes with installation manual and it clearly tells you the method to vacuum it before opening valves. Even gives you the pressure readings that have to be achieved.
Just to clarify, there used to be an electrician who had a shop nearby my home, the 14 years ago Dawlance was installed and serviced by him and that time i didn't know anything about vacuum pump (i was 16 that time) but i remember he always brought a pump with him. So there are always people who go by books and provide quality work and then there are those who are jugarri baz.
