The hoses will not survive boiling temps. Better to just get some more Star San and do it up right.
I also use a push of PBW, rinse water, then Star San solution in my lines, from the keg that just kicked. Since I'm typically cleaning the keg out anyway (using the same solutions) it just makes sense to run some through the lines (plus it goes through the liquid dip tube). I use another CO2 source for this, so that I don't have to even think about reaching in for the gas lines (brew fridge, not kegorator/keezer).