The BlueBox 4-pipe multi-purpose units are able to meet simultaneous and independent heat loads of the opposite sign, with the advantage of working in heat recovery operation: whenever there is a simultaneous demand for cooling and heating,  the multi-purpose unit will work in recovery mode, and move the thermal energy from rooms that need to be cooled to those that need to be heated.

If the two heat loads are not balanced, then the controller works in mixed mode to recover as much thermal energy as possible and use the air exchanger as heat source with which to exchange the missing amount of capacity for meeting both demands of the system.  The 4-pipe multi-purpose unit can therefore work indirectly all year round to meet all the thermal and cooling energy demands of the system, with the additional significant advantage of waste heat recovery.

Depending on the various scenarios that can occur over the span of a day, the multi-purpose units can work with different modes and change from one to another fully automatically.