50 Plate Small Water to Water Heat Exchanger - 3/4" Ports - American Royal For use with outdoor wood boilers, snow melt, solar systems, and many other applications. Overall dimensions: 3" wide, 7.5" long. See our ad for 50 plate 5"x12" for home heating. Maximum pressure 435. Maximum temperature 392 degrees Fahrenheit. The feed and return is 3/4" MPT. Our superior brazed plate style water to water heat exchanger features 316 stainless steel and are FOOD GRADE AND POTABLE WATER CERTIFIED!