Everything looks good in the drawing and in the print preview. However when printed the dimensions text is very faint. Right size but very faint. I can adjust the text size, but it still prints very faint.
As text size comes out right and the other dimension elements appear not too faint I suspect it has to do with line width. It is typical for line width 0 to disappear completely in a pdf, also depending on the pdf-viewer. Check the overall line width of the dimension and change to maybe 0.25 mm if it is 0.
This is because the line width of dimension extension lines, dimension lines and arrows or ticks can be set in Options - Current Drawing Preferences - Dimensions in a different value than the general line property of the whole dimension, which is handled as a block.
So the general line width setting for the dimension only governs the text absolutely. Awkward, but that's how it is.
If in Current Drawing Preferences - Dimensions line widths are set as By Block (default, I think), these elements will have the same line width as the text, as the general line width property of the dimension.