Roof-mounted modular heating, ventilation and air-conditioning system (HVAC) to supply 30kW cooling and 10kW of heating, to ensure a cabin temperature of 25°C max in a 60°C ambient provided the coach is thermally insulated. The HVAC system is a dual circuit design with dual compressors (15kW x 2) for redundancy and capacity control. The system has 10kW electric heating which can easily be increased to 20kW should a very low ambient of below -20°C be applicable.

The HVAC system does not restrict the standard operational features of any coach type and stays within the standard gauge set. The stainless and aluminium fabricated HVAC unit is protected with a sheet metal cover that matches the style and colour of the coach. For best results, two rooftop HVAC units must be installed per coach (60kW total cooling), one on each end of the coach. The rooftop HVAC system is qualified to international standard EN15085.

All electrical components and switchgear are housed in the control panel installed in the electrical control room of the coach, with limited electrical parts in the rooftop unit. This means that faults can be determined without needing access to the rooftop HVAC unit. All faults and trips can easily be addressed from the accessible control box, without needing to open the rooftop HVAC unit.

All electrical connections, looms and the electronic control panel, as well as electrical control gear, are designed and selected for operation in the railway environment, which include adverse temperatures as well as severe shock and vibration.

The HVAC unit is equipped with custom-designed electronic controllers, with extra safety features for the extreme maximum ambient of 60°C. The touch screen controller activates subsystems as required to regulate the cabin temperature to the desired setting on the control panel (HMI). The system has a Bluetooth login interface for remote monitoring via a smartphone app and/or laptop.