I am replacing two threaded 1/2" boiler valves, and I'm unsure of how tight they should be. I know with faucets that I've changed, the instructions often say something like hand tight and then 1/4-1/2 turn with a wrench. I haven't changed many valves before, so I don't have a lot of experience. My plan is to apply Teflon tape, then thread sealant, and then tighten them. I just don't know how tight they're supposed to be, other than I know it's bad to bottom out the threads. If anyone has any tips or suggestions, I would really appreciate it!