Abstract: Tunnel freezer for freezing products which are transported through the tunnel freezer from an infeed end to an outfeed end. Close to the outfeed end of the tunnel spray nozzles are provided for spraying the products with liquified nitrogen or similar cryogenic liquid. The tunnel comprises circulation fans positioned upstream of the nozzles. The circulation fans comprise at least one paddle wheel positioned immediately above the products. The paddle wheel has paddles, the radial length of which is 20 to 60%, preferably 50%, of the radius of the fan wheel. Preferably also a fan wheel is arranged below the conveyor between the two paths of the conveyor, whereby the paddle wheel is driven by e.g. a chain or belt transmission. Moreover, the tunnel is divided in compartments by partitions, whereby the partition positioned at the infeed end of the fan wheel is positioned closer to the fan wheel than the partition which is positioned at the outfeed end of the fan wheel.