A temperature conditioning system for a lithographic apparatus. Temperature variations in an object cause object deformation which prevents the object being accurately positioned. Temperature condition systems use conduit systems, provided with fluid, in or on the object to control the temperature of the object to reduce object deformation. In this way, parts of the object can be more accurately positioned. However, acceleration of the object and the temperature conditioning system induces variation in pressure within the fluid inside the conduit system on or in the object, which may also cause object deformation. To provide an improved conduit system, the lithographic apparatus further includes a control system which is used to control the movement of the object based on measurements indicating pressure variation in the conduit.