What good is then new units come with factory prefilled gas ? May as well sell 'kosong'

This post has been edited by mini orchard: Mar 15 2022, 04:01 PM

I mean after connecting outdoor unit to indoor unit but before releasing the prefilled refrigerantt in the compressor into the line set, they purge the air by charging the lineset only with some gas and then loosen the nut fitting slightly to push out the air in the lineset). Or is this step not even done?

In the service manual they are supposed to vacuum the line set before opening the service valves that will release the prefilled gas. They will always be some air in the lineset since they are open to the atmosphere before connecting the outdoor and indoor unit.


You seem like a tech in hvac? If so can tell me why most tech here seem to not even vacuum the lineset and don’t have issues with moisture and air in the system after a while?

This post has been edited by diffyhelman2: Mar 15 2022, 04:50 PM

I am not an expert but from my understanding with few technical people from factory, moisture is not a big concern in the line set. They are more worried in little insects if both ends are not tape if prolong unused.

In addition, I think all AC should have this ....