RE: Do we change filter driers on units that have them inside the condenser?
Gonna have to disagree with previous posts unless a valid explanation is given.
If you’re opening the system to the atmosphere only for a swap or repair, not a burn out obviously, anything that is behind the condenser valves is isolated and the rest gets cleaned up on evac.
When you open the valves after having pulled a good evac (I just wrote a long post on it), nothing has changed. It’s like you just did a pump down and released the gas right back. There should nothing else than oil and refrigerant in the pipes, so why change the drier if it wasn’t exposed to ambient air ?
Now if the drier is outside the condenser, the only answer is yes; change it.