Well... he fails combat and discards cards as damage?
Keep in mind, he ONLY recharges weapons (instead of discarding), when he *plays them for the weapon's own power*! If any sort of damage knocks that weapon into discards - it stays there.
(That said, dying with Valeros in RotR is really very unlikely, as opposed to failing a scenario because his small hand was getting clogged with weapons and armor, and he couldn't explore fast enough so you failed the timer)
If he discards a Weapon for its power he may recharge it, regardless of whether or not the check is successful. But if he fails that check, he'll (likely) take damage and have to discard some cards. Any Weapons remaining in his hand that are discarded for damage are not recharged because they aren't being discarded for a power on the card.
There are other times he might discard cards as well, like at the end of the turn so he can draw other cards. He doesn't get to recharge those either.
Similarly, he might have a Weapon he buries for its power. He doesn't get to recharge those; they have to be discarded for his power to work.
Note that - especially for party sizes larger than 3 or 4 - character death is very rare in PACG. For most players and most games, the difficulty comes from beating the scenario in enough time, not dying.
Though they kind of have a bit of overlap. If you're close to dying, you tend to discard less cards and explore less, which means you are slower to win.