It is possible to purchase a FU 15 heat pipe unit with filter, which is connected to the VPL 15 unit.
The heat pipe slightly raises the temperature of the outdoor air, thereby increasing the heat pump’s efficiency in the VPL 15 aggregate significantly during the winter.
With an integrated FU 15 heat pipe unit, in most cases there is noneed for a heating coil with mixing circuit.
NB! The heatpipe is not a recuperative or regenerative heat exchanger, and is therefore not submitted to the requirements of a temperature efficiency, it is however accounted for in the calculations of COP for the VPL15