Thanks I was not sure if the unit had a oil in it since they said dry charge.
I understand what you said about brazing first then releasing the charge and pulling a vaccum.
But their is two things I'm not to sure about. one Don't I have to take out the sharder valve seats from the compressor first before I braze or I can damage them? Second since I need to put in a new orfice size in my evaporator .71 because I have a 2.5 ton unit and a 3 ton A- Coil, is there going to be a problem once I release the nitrogen out of the system? I have to open up the old system to put in the new ofrice and install a new liquid line dryer. I'm concerned about damage to the high side and low side valves on the condensor. Or do I just leave the nitrogen in the compressor braze everything and then release and vacuum.
If you know of any other way to do this with the right tools and equipment please let me know.
Such as a core removal tool etc, etc.
Another question if I didn't have to add these extra componets, do hvac techs add nitrogen to the system then braze to prevent flaking inside and possible damage to the system.
Please answer my question in the order I presented them to you so that I may understand.
I have a very strong electrical back ground but
only a limted certification in hvac up to 2 ton units that I worked on and only when the need arises.