20 Plate Water to Water Heat Exchanger - 5" x 12", 1" MPT Ports - American Royal For use with outdoor wood boilers, hot water recirculation systems, snow melt, solar systems, and many other applications. Overall dimensions: 5" wide, 12" long Maximum pressure 435. Maximum temperature 392 degrees Fahrenheit. The feed and return is 1" MPT. Our superior brazed plate style water to water heat exchanger features 316 stainless steel and are FOOD GRADE AND POTABLE WATER CERTIFIED!