I have the Helios 9 with the 10W head. Somehow, during a dive I managed to unscrew the beam adjuster out and flooded the light. There is supposed to be a limit-stop preventing such action, but either I didn't notice it or it didnt work. Either way, the the limit aduster didnt and the light flooded, .
Back on board, I unscrewed the lens, rinsed with fresh water, drained and dried the interior in the sun. It worked the next day! Well upon ressembly - the bulb must have been not seated correctly or the limit adjuster was in too far, cause I crushed the bulb out case. The light still worked! I sent it back for a rebuild, and it's less than 30 days old, so we'll see how they handle this. I take responsibility for the bulb, I guess, but the limiter should have prevented me from unscrewing the beam adjuster.
I'll repost on how this turns out...