I have decided to test just the effectiveness of the heat-pipe header’s ability to transfer heat to a condenser pipe inserted through it. I have built several prototypes that use geyser pumping to transfer the working fluid through the heat-pipe condenser, but the results were confusing, so I’m going to decouple the problem by eliminating the geyser pumping in lieu of an electric pump that will pump the tank water through the heat-pipe condenser and back to the tank.