The OEG heat pipe vacuum tube collector 4flex is one of the most modern solar tubes and satisfies highest demands on efficiency, safety and flexibility.
In the 4flex solar tubes there is a copper absorber in a vacuum glass tube. Due to the vacuum, heat losses are minimized, like in a thermos flask.
At the rear side of the absorber there is copper pipe also placed in a vacuum: the heat pipe. It is filled with a little amount of working fluid. The vacuum inside the heat pipe causes the fluid to vapourise starting from a temperature of 28° C.
With solar radiation, the absorber takes up the energy and warms up. This is when the working fluid in the heat pipe starts to boil and changes from a liquid to a gaseous state. The resulting vapour rises to the top end of the heat pipe into the capacitor. Via the capacitor the heat pipe conveys the heat to the solar liquid and the working fluid condenses again and flows back down through the copper tube. If there is sufficient sun radiation, this cycle is repeated continuously..
The dry connection of the heatpipe tubes in the 4flex headers, the small amount of working fluid and this patented overheat protection ensure a particularly high operating safety of the 4flex. Due to the dry connection, individual tubes can be exchanged if necessary without having to drain the solar liquid from the solar unit. Modern click-fit technology allows fast, easy and flexible one-man assembly. Individual tubes can be plugged together in order to generate solar collectors of a perfectly aligned size.
