Laundry hot water supply coil assembly

For use in a laundry dryer and clothes washer combination;

• a coil for liquid such as water to be inserted in the heating unit of a dryer to derive heat therefrom to heat water flowing through the coil;
• the coil comprising, fluid inlet and outlet ports interconnected by a plurality of generally straight and spaced apart runs, each run having opposite ends interconnected by returns connecting said runs in series with each other between said inlet and said outlet ports, said runs including upper and lower sets of runs, the runs of each set lying generally in a common plane with the other runs of the set and the planes of the two sets of runs being generally parallel and spaced from each other;
• said runs having formed internally throughout the length thereof a continuous spiral groove for conveying liquid such as water through the coil, and wherein said runs are formed from metallic tubing and wherein the outer surface of the runs are configured in a shape as a spiral protrusion complementary to the spiral groove of the runs and extending coextensively and continuously with the spiral groove in the same direction as the spiral groove.