VRF // R2-Series

The R2-Series
Simultaneous heating and cooling with heat recovery

In a world-first innovation, the R2-series enables simultaneous heating and cooling with only two pipes. Thermal energy captured during cooling is used to heat the other rooms. In hotels and large office complexes in particular, this represents an extremely energy efficient solution. It is also highly convenient, with each user free to decide whether they wish to heat or cool their room.

Efficiency is further increased through the use of special booster and heat exchanger units, which can heat drinking water to as much as 70 °C.

Ideal for use in:

  • Hotels
  • Large office buildings


  • Excellent flexibility
  • Customised comfort through simultaneous heating and cooling
  • Highly convenient mixed operation – no need to stop compressor when switching from cooling to heating

Simultaneous heating and cooling with only two pipes: how it works.

VRF systems normally use a 3-pipe solution for simultaneous heating and cooling. This includes the suction pipe, the liquid pipe and a third pipe containing refrigerant in the form of hot gas. But since the City Multi VRF R2-series uses a special BC-Controller for phase separation of the refrigerant, these systems only require two pipes.

BC-Controller – the innovative centrepiece

The BC-Controller is the core component of the R2 system and distributes the refrigerant. Up to 50 indoor units can be connected to just one outdoor unit via the BC-Controller using just two pipes.

Heat recovery with the R2 series

All facts and benefits at a glance:

Less installation work
Two pipes mean less installation work since fewer soldering joints are required.

Lower leak risk
As there are fewer connection points in the system, this reduces the potential for leaks.

Large scale
Up to 1,000 m of pipe can be laid and a maximum of 2,000 indoor units controlled centrally. With water-cooled R2 systems in particular, the recovered heat is released into a water network and can be stored if required.

Further information on the City Multi outdoor units is available here.

VRF outdoor units