Calefactio HGT-15 non-potable thermal expansion tank is suitable for water heating system such hydronic water/glycol radiant floor and solar water heater FEATURES AND BENEFITS Strong welded construction Welded steel construction is designed to withstand high pressure loads and adds safety to your installation. Tanks are sturdy and built to last while at the same time they are lightweight, easy to handle and simple to install. Resistant electrostatic paint finish Provides an attractive look in addition to being durable as the finish is obtained through an electrostatic paint process. Full acceptance bladder Withstands high temperatures. Of heavy duty construction, manufactured in house through an injection molding process. Compatible with water/glycol mixtures (up to 50%), solar and cooling systems. Factory precharge on all models Suits most common installations. The precharge must be manually adjusted on site.