A ventilation fan (200, 400), comprising: - a shaft having a shaft body (260, 462) extending between a first shaft end (262, 464) and a second shaft end (264, 466); - an impeller (212, 414) having an impeller first portion (270, 470) disposed about the shaft and disposed proximate the first shaft end and an impeller second portion (272, 472) extending from the impeller first portion, wherein said impeller second portion includes a fan blade (276, 476); - a vane (310, 490) downstream the fan blade in the main flow path of the fan; - a motor housing (216, 416) disposed about the shaft and axially spaced apart from the impeller, the motor housing having a platform (296, 484) of the vane, a housing arm (290, 480), and a housing leg (292, 482) extending from the housing arm; - a first bearing, which is an air bearing (330, 520), that rotatably supports the first shaft end (262, 464), the air bearing being disposed proximate the first shaft end and disposed between the housing arm and the shaft; - a bearing housing (218, 418) disposed about the shaft and disposed proximate the second shaft end, the bearing housing extending between the vane platform (296, 484) and a second bearing (332, 422, 522) that rotatably supports the shaft; wherein an inner surface of the air bearing and an outer surface of the shaft define an air bearing flow path (340, 530), the ventilation fan being characterised in that - the second bearing is a rolling element bearing, and - the impeller first portion has a hole that makes an impeller port (274, 474), the ventilation fan being further characterised by one of the two following options: - a first opening is defined between respective ends of the impeller second portion and the vane platform, and the first opening makes a fluid communication between the main flow path of the fan, the air bearing flow path and the impeller port to define a flow path; - the vane platform extends from the housing leg, the vane platform has a hole that makes a housing port, the housing port being disposed upstream of the vane in the main flow path of the fan, and the housing port makes a fluid communication between the main flow path of the fan, the air bearing flow path and the impeller port to define a flow path. - a shaft having a shaft body (260, 462) extending between a first shaft end (262, 464) and a second shaft end (264, 466); - an impeller (212, 414) having an impeller first portion (270, 470) disposed about the shaft and disposed proximate the first shaft end and an impeller second portion (272, 472) extending from the impeller first portion, wherein said impeller second portion includes a fan blade (276, 476); - a vane (310, 490) downstream the fan blade in the main flow path of the fan; - a motor housing (216, 416) disposed about the shaft and axially spaced apart from the impeller, the motor housing having a platform (296, 484) of the vane, a housing arm (290, 480), and a housing leg (292, 482) extending from the housing arm; - a first bearing, which is an air bearing (330, 520), that rotatably supports the first shaft end (262, 464), the air bearing being disposed proximate the first shaft end and disposed between the housing arm and the shaft; - a bearing housing (218, 418) disposed about the shaft and disposed proximate the second shaft end, the bearing housing extending between the vane platform (296, 484) and a second bearing (332, 422, 522) that rotatably supports the shaft; wherein an inner surface of the air bearing and an outer surface of the shaft define an air bearing flow path (340, 530), the ventilation fan being characterised in that wherein an inner surface of the air bearing and an outer surface of the shaft define an air bearing flow path (340, 530), the ventilation fan being characterised in that - the second bearing is a rolling element bearing, and - the impeller first portion has a hole that makes an impeller port (274, 474), - a first opening is defined between respective ends of the impeller second portion and the vane platform, and the first opening makes a fluid communication between the main flow path of the fan, the air bearing flow path and the impeller port to define a flow path; - the vane platform extends from the housing leg, the vane platform has a hole that makes a housing port, the housing port being disposed upstream of the vane in the main flow path of the fan, and the housing port makes a fluid communication between the main flow path of the fan, the air bearing flow path and the impeller port to define a flow path.