I just bought a setup like yours and only know what I read in https://www.cannabisbusinesstimes.com/article/butane-extraction-tips/ TIP: Run until the solvent appears colorless.
“When observing your solvent flow through the sight-glass, it should appear yellow as it first passes through the plant material. Once it’s grabbed everything good and deposited it into your collection pot, the solvent will appear colorless.”
If you do not have a sight tube then you may want to get one. I am thinking of doing so.