Abstract: A cooling system for a vehicle cab where the vehicle has an internal combustion engine is provided. The system comprises a cooling chamber having an ambient air intake, and first and second pairs of sorption vessels. Each pair of sorption vessels comprises a first sorption vessel containing a sorption solution which is located in the cooling chamber and is in fluid communication with a second sorption vessel located outside the cooling chamber. The system further comprises first and second cooling circuits, each circuit containing a coolant and being in heat exchange contact with a respective one of the second sorption vessels. A first control valve selectively directs coolant from the first or the second cooling circuit towards the cab. An exhaust passage conveys exhaust gases away from the engine, and the exhaust passage has at least one exhaust aperture in communication with the cooling chamber.