At the moment there are two tags related to fans:
If you look at the topics there is no distinction which fans are meant, this must be read in the questions.
Should we create separate tags for specific fan applications?
There aren't that many topics labelled with either one of the existing tags, so re-tagging will not be a problem.
Indeed these tags are generic tags and do not cover the range of fans specifically for the application they are used for. There are 3 types of applications for fans in 3D printers,
How about making 3 categories and re-tag? (in the same order as the previous list)
Alternatively, we could just use a single tag and let the poster make sure that he explains clearly which fan is used.
3 tags is probably overly complex. I've not looked at the question list but I expect that these questions should also have a print quality or electronics tag, making the categorisation of the question fairly clear. The problem to me of having several tags is choosing which one would be relevant to a question, and also having to literally look through all the individual tags if you were looking for a question that matches a certain type of issue.
Looking at the questions so far, the vast majority are discussing the part cooling fans, or the distinction between part cooling and extruder/heatbreak cooling. I don't see any questions about specifically cooling the circuit board as was indicated in the tag wiki for print-fan.
Given the potential confusion about what a fan is for, and the lack of a need so far to identify questions about PSU cooling, a single fans tag still makes sense.