Watts 0066605 2.1-Gallons Non-Potable Water Expansion Tank 1/2" MNPT

The Watts 0066605 Non-Potable-Water Expansion Tank is an essential part that will help to get the most out of the HVAC system and its service life. This tank has a 2.1-gallon capacity for use within non-portable water such as those used in hydronic heating systems, solar thermal loops, and chilled water systems. Its main purpose is to take the pressure variation in these systems because of temperature differences. When the water in the system has been heated the volume also increases and the expansion tank has been designed to do so it will safely contain this extra volume.