The A.O. Smith® BTPD models feature all stainless steel tank construction and are designed for heating deionized water. The tank and other wetted components are suitable for deionized water.

These units are designed for industrial and process water applications and are not recommend normal potable water heating applications. For potable water heating applications A.O. Smith® designs and builds a long list of other models to choose from. This is a process water heater producing non-potable water, and therefore does not need to meet current edition ASHRAE/IESNA 90.1 or C.E.C. energy guidelines.