I don't know about your setup or circumstances, but HD cleaning is very basic. Just a blast or two will do. If you need more than that, please explain. HDs are "sealed units" and you don't want to compromise the "air exchange pressure filter" and if you do that's a soon to be broken HD(rare). So, don't go crazy cleaning a HD if you use some compressor type setup. Of course, you can clean the surrounding area and if the frt. panel has a filter or hidden from view, clean the inlets as well. Frt. panels can be removed or accessed for cleaning, just check the manual or support website for instructions of access.