100 Plate Heat Exchanger - 5" x 12", 1 &frac14;" 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!