Abstract: A heat exchanger for refrigerator evaporators of the type consisting of helically coiled refrigerant-carrying tubing with radially inward extending fins formed along the length of the coiled tubing, with the air to be refrigerated directed across the axis of the coil turns. The coil turns are skewed from the helix angle to expose a greater proportion of the fins into the air flow path between the coil turns so as to increase the air flow contact with the fins. The skewing is created by relatively offsetting opposite portions of the coil turns along the air flow path across the helical coil to increase the obliqueness of a portion of each coil turn with respect to the direction of air flow.