Abstract: A mobile heater for aerospace ground equipment includes a diesel engine for continuously driving a centrifugal blower for introducing air into a plenum chamber so that the air is not contaminated by the diesel engine. The diesel fuel is utilized with a unique burner arrangement, which enables burning within a burner body or can without build up of carbon, having a portion of the air supplied to the plenum chamber supplied thereto. The hot products of combustion from the burner arrangement flow into a core of a heat exchanger where they are directed through longitudinal spiral slots which terminate inside of a shell of the heat exchanger from which they are vertically exhausted upwardly through an exhaust stack. Ventilating air from the plenum chamber is directed through a nest of formed arcuate tubes, which have common walls with the longitudinal spiral slots whereby heat is transferred through the common walls to heat the ventilating air.