>all you need Not at all that simple. As already mentioned in the thread, they had limited fuel. Boiling 100s if not 1000s of gallons of water takes more fuel

>all you need Not at all that simple. As already mentioned in the thread, they had limited fuel. Boiling 100s if not 1000s of gallons of water takes more fuel they already don't have. SWAG: they probably weren't just using distilled water. There was likely some pH additive or other chemical treatment that water uses for a multitude of factors (scaling, corrosion, erosion, foaming, etc etc) that gets lost if you just vent water overboard - lost physically as volatile chemicals are vented or lost logically as new water must be treated. Also, the boiling process itself is much more complicated than a pot and a fire. To achieve any reasonable amount of efficiency at all requires a multistage process with heat reclamation. If you plan on transiting salt water, the boiling process produces a thick, salty effluent that can be difficult to pump and is strongly corrosive. The weight, complexity, training, parts inventory, etc are all large costs. These are all hard sells for relatively short voyages.