Anderson - Snow Corporation manufacturers a coil that solves this problem! ANSCOR offers a coil fabricated from either 5/8", 3/4" or 1" O.D. tubing with flat plate type fins. Fin spacings are available from 4 to 14 fins per inch, with a fin thickness of either .010", .016" or .025". This heavy fin is available in Copper, Aluminum, Type 304 or Type 316 Stainless Steel, Monel, Carbon Steel and Cupro-Nickel. The heavy wall tubing used in conjunction with this fin is also available in the above materials from .028" to .120" wall. This heavy fin can take more abuse without the fins collapsing. The wide fin spacing also makes plugging less likely to occur. The heavy wall Stainless Steel or Carbon Steel tubing offers a fully welded tube to header joint. The coil is available in 1, 2 or 3 rows, either standard steam or steam distributing (tube within a tube type) coils.