Solar expansion tanks play and important role in a properly designed solar water system. The expansion tank will absorb the extra pressure that occurs when a system goes into stagnation. It is important that a properly sized expansion tank be installed in all solar heater applications for safety and durability of the system
We use Zilmet Solar Expansion tanks that we import from Italy. They have a high temperature EPDM rubber bladder that can with stand the high temperatures of a solar heating system. Never use a regular hydronic expansion tank as it will break down under solar heating conditions.