Cabin pressurization system for agricultural machines, having a filtration system

Cabin air treatment apparatus for an agricultural machine, comprising at least one external air inlet, a filtration system connected downstream of the external air inlet, an HVAC system connected downstream of the filtration system, said HVAC system comprising an HVAC blower, and a cabin air supply outlet connected downstream of the HVAC system,

• wherein the cabin air treatment apparatus further comprises a box inside which the HVAC system is housed, said box having a levelling opening for placing the box into communication with a cabin of the agricultural machine to level a pressure inside the box with a pressure inside the cabin,
• wherein said at least one external air inlet comprises a first external air inlet and a second external air inlet both formed on the box, said first external air inlet and second external air inlet being in selectively enabled or disabled communication with the HVAC system, and
• wherein the filtration system comprises:
• a first filter for effecting a filtration of dust, aerosols and vapours, arranged at the first air inlet,
• a filter blower for drawing air from the first external air inlet and delivering it to the HVAC system, said filter blower being arranged directly connected downstream of the first filter and inside the box, the filter blower being distinct from the HVAC blower, and
• a second filter for effecting a mechanical filtration of dust, arranged at the second external air inlet, wherein the filter blower is not arranged downstream of the second filter, air being drawn through the second external air inlet and second filter by the HVAC blower.