Zilmet ZHT18-30 Hydronic Expansion Tank 1/2" NPT 4.8 Gal

The Zilmet ZHT18-30 Diaphragm Expansion Tank is a 4.8-gallon pressure management component used to accommodate thermal expansion in closed-loop water heating and hydronic systems. Featuring a 1/2" NPT connection, the tank is commonly installed in HVAC systems to help regulate pressure fluctuations caused by temperature changes during operation. Its diaphragm-effective construction separates air and water within the tank assembly, while its role within the system includes supporting pressure stabilization assisting with equipment protection and helping maintain consistent fluid circulation in compatible heating applications.