Method for annealing level-wound coil

The present invention provides a method for manufacturing a level-wound coil comprising a phosphorus-deoxidized copper pipe for piping, etc., wherein it is possible to effectively remove a carbon film that forms in the pipe without increasing manufacturing cost or environmental problems, and it is possible to suitably obtain a copper pipe having durability against pitting corrosion in cold water by performing a novel tempering and annealing process that can be suitably applied to a process for coiled copper pipes. The copper pipe comprising phosphorus-deoxidized copper to which a prescribed drawing process is applied is wound into a coil, and the resulting level-wound coil is annealed by sealing hydrogen gas having a purity of 90% or greater in the copper pipe of the level-wound coil, and then heating the level-wound coil to 350-500°C in a reducing atmosphere or an inert atmosphere.