Abstract: A water distillation apparatus having a feed water pre-heater, an evaporator tank, and a storage tank. The storage tank has an upper surface and depending walls, the pre-heater and evaporator tank being on the upper surface, and extending, with the other components, to approximately the same height, all components being within the periphery of the walls. A mixing vessel including a level controlling overflow pipe receives water from the pre-heater, and a short, straight, large diameter conduit connects the mixing vessel and evaporator tank. The mixing vessel contains a valve to drain it and the evaporator tank. The pre-heater comprises two dished elements in facing relation, with a divider plate between them, the elements being joined at their peripheries. A serpentine path is provided in each of the two spaces of the pre-heater, formed by a pair of L-shaped separators extending linearly from one end of the space to a point spaced from the other end.